General Factors

The Aliens

The Aliens are the main foe in XCOM: Enemy Unknown, consisting of several species united under a specific agenda that will conduct hostile missions regarding Earth and humanity. The aliens will deploy their ground forces using Unidentified Flying Objects (UFOs), which can be detected and shot down by XCOM.

The most important aspects regarding the aliens are:

Escalation - every month the aliens will introduce better armed species and UFOs, increasing their deadliness.

Retaliation - They will strike back against XCOM by attacking your satellites if their UFOs are ignored and in the Enemy Within DLC they will assault XCOM's HQ if their base on Earth is destroyed by your forces.

Determination - they will keep conducting their missions and terrorizing Earth until the Council that supports XCOM is disbanded and they complete their objectives.

As you progress through the game you'll encounter new aliens and discover more about their horrific intentions, as you conduct interrogations and autopsies and research their advanced technology. As XCOM Commander it is your mission to stop their actions and use the knowledge gained through research stop the alien invasion of Earth.

The aliens species can be assigned to 3 roles: Commanders, Soldiers and Secondaries.

Commanders only appear on UFOs and Storyline missions.

Soldiers are general use troops deployed to any type of mission and holding plasma firearms.

Secondaries are usually heavier alien units with specialized roles such as melee or robotic units with a more restricted appearance.





XCOM Goals

In order to win the game, XCOM commanders will have to achieve two goals:

Prevent 8 or more countries from leaving the Council

The game will continue endlessly as long as you have 9 countries still in Council. You can keep playing until 2039 or 2084 if you wish to do so, as long as you don't complete (or fail) some of the key missions (see below).

Unlike the original game, you can't lose from repeatedly getting a negative grade on the Council's monthly report or running out of funds. However, if those situations keep happening then most likely you'll lose since panic will spiral out of control and make countries leave the Council.

The higher the difficulty level, the harder it will be to control panic.

Keep in mind that retaining at least 9 countries in the Council doesn't necessary imply covering them all with satellites, although you'll want to expand your satellite network as much as possible due to the benefits it will provide.





Complete the Game Objectives

To achieve the game objectives you'll have to fulfill a number of subobjectives in sequence. For more details see Game Objectives.

Theoretically, you'll only need to complete 5/6 key Storyline missions to win the game: the 1st mission (either the Tutorial or a regular Abduction), capturing the 1st alien and an Outsider alien, Alien Base Assault, XCOM Base Defense (on the Enemy Within DLC), Assault the Overseer UFO and Temple Ship Assault.

If you fail to finish the 1st mission, Alien Base, Base Defense and Temple Ship you'll be given the opportunity of replaying the mission or losing the game.

With the exception of the 1st mission (and to some extent, the XCOM Base Defense), you can delay those missions as much as you want. However, as months pass the aliens will deploy more capable units, which can increase, or not, their difficulty, depending on how far you've progressed on your own weapons/armor research.

Besides the progression in the timeline, the difficulty levels will also have an effect on the number and type of the aliens present during missions and their individual stats.





Difficulty Levels & DLCs

The Difficulty levels can have a major influence on the type of strategy chosen because of the specific changes they introduce. For details on their influence over funding, alien stats, etc., see Difficulty. For specific information about how difficulty levels change the number of aliens during missions, check Alien Deployment.

The difficulty will be further increased if playing with Ironman, since it makes it impossible to reload a saved game to and fix a mistake such as satellites not being ready on time for launch at the end of the month.

The Second Wave or the Slingshot and Enemy Within DLCs also can bring changes to the game, as described below.

Second Wave

Strategic Layer Changes

New Economy - randomizes the funding given by each country. The starting credits may be completely different from the regular values.

- randomizes the funding given by each country. The starting credits may be completely different from the regular values. Marathon - everything takes longer to complete (research, manufacturing, etc) and appearances of new alien species will also be pushed forward.

- everything takes longer to complete (research, manufacturing, etc) and appearances of new alien species will also be pushed forward. Results Driven - funding is reduced by the country's current panic level.

- funding is reduced by the country's current panic level. High Stakes - scientist/engineer rewards from Abduction missions are randomized, can make impossible some strategies that depend on these rewards.

- scientist/engineer rewards from Abduction missions are randomized, can make impossible some strategies that depend on these rewards. Diminishing Returns - massive cost increases for satellites.

- massive cost increases for satellites. War Weariness - funding trickles down to 0 over time.

- funding trickles down to 0 over time. E-115 - can lead to Elerium shortages for building projects.

- can lead to Elerium shortages for building projects. Alternate Sources - base facilities cost more power, meaning less space and more building costs.

- base facilities cost more power, meaning less space and more building costs. Not Created Equally , Hidden Potential and Training Roulette - randomize soldier's stats, their progression when promoted and their abilities. Can be used to create super soldiers, or severely limit them.

, and - randomize soldier's stats, their progression when promoted and their abilities. Can be used to create super soldiers, or severely limit them. The Greater Good , More Than Human and Mind Hates Matter - restrict use of Psionics.

, and - restrict use of Psionics. Total Loss - causes KIA soldiers to lose all their equipment, forcing you to spend resources to replace it.

- causes KIA soldiers to lose all their equipment, forcing you to spend resources to replace it. Save Scum - actually helps more since it can be used to ensure that shots hit their targets. Can also be used to randomize results of air combat dogfights and the appearance of several events/missions.

Tactical Layer Changes

Damage Roulette - dramatically increases shot randomness.

- dramatically increases shot randomness. Not Created Equally , Hidden Potential and Training Roulette - randomize soldier's stats, their progression when promoted and their abilities. Can be used to create super soldiers, or severely limit them.

, and - randomize soldier's stats, their progression when promoted and their abilities. Can be used to create super soldiers, or severely limit them. The Greater Good , More Than Human and Mind Hates Matter - restrict use of Psionics.

, and - restrict use of Psionics. Absolutely Critical and Aiming Angles - make flanking shots more deadly and accurate. Can work either for or against you during a battle.

and - make flanking shots more deadly and accurate. Can work either for or against you during a battle. Red Fog and Total Loss - increases the penalties for having injured or KIA soldiers.

and - increases the penalties for having injured or KIA soldiers. Itchy Trigger Tentacle - non-cover aliens become more deadly. When facing Sectopods/Cyberdiscs this can lead into very nasty encounters when you activate them. Save Scum - can actually help since it can be used to ensure that shots hit their targets.

- non-cover aliens become more deadly. When facing Sectopods/Cyberdiscs this can lead into very nasty encounters when you activate them.

Enemy Within DLC

A new resource called Meld is introduced, allowing to perform cybernetic and genetic modifications for your soldiers.

research time is increased on the Classic/Impossible difficulties by 40% and 70%, respectively.

The plasma weapons building costs are also increased on average by 50% of their previous cost.

A new foe, EXALT is added, which can be an hassle to XCOM.

Also adds the Base Defense mission.





Slingshot & Progeny

There are also two optional DLC campaigns available as Council missions. If the 3 missions of each are completed successfully they give access to advanced resources, making the game easier. Completing some of their missions can be challenging though.

Both campaigns also provide large amounts of scientists/engineers, as well as credits and other Alien Artifacts.



Starting Base Location

The location of the XCOM HQ automatically deploys a satellite over the country and gives the continent's specific bonus to the player and will have a major impact on the early game. Each country covered with a satellite provides additional Scientists or Engineers, besides credits (§), that are received at the end of the month and can be very useful in gathering enough Engineers to be able to build Laser Weapons after they are researched.

If you cover an entire continent with satellites, then you also get that continental bonus even if your base is located elsewhere. Choosing which continent will be the first fully covered by satellites is another key move of the early game. Losing a country on a continent due to it leaving the Council automatically means the end of the bonus.

The starting bonus can never be lost, even if the country where the XCOM HQ is located decides to leave the Council.

Country Funding by Continent (+50% Easy difficulty) Africa Asia Europe North America South America Egypt: §70

South Africa: §80

Nigeria: §100 China: §100

Japan: §100

India: §60

Australia: §60 United Kingdom: §100

Russia: §150

France: §80

Germany: §100 United States: §180

Canada: §100

Mexico: §50 Argentina: §70

Brazil: §80 Ʃ §250 Ʃ §320 Ʃ §430 Ʃ §330 Ʃ §150 All In

Monthly XCOM funding increased by 30%. Future Combat

All projects in The Foundry and the Officer Training School cost 50% less. Expert Knowledge

Labs and Workshops cost 50% less to build and maintain. Air & Space

All aircraft and aircraft weapons cost 50% less to purchase, build and maintain. We Have Ways

Autopsies and Interrogations are completed instantly.

The bold country is where the base will be located if you pick that continent to start the campaign.

HQ's Areas

After selecting the game's difficulty and the starting location for your HQ, managing the operations at the XCOM Headquarters is the next step for any strategy to achieve victory over the aliens. HQ has six main areas, all accessible by the Base View, each with specific priorities and requirements that affect one another, as listed on the table below.

Detailed descriptions of how to achieve the tasks described may be found in the following sections.

Situation Room

The Situation Room is where you'll manage all aspects directly related with the Council, as launching satellites, managing funds and checking the current panic levels and storyline objectives. The Situation Room will be unlocked after you complete your first Alien Abductions mission.

For a description of the required steps to win the game see Storyline and Storyline Missions.

For a description of the interactions with the Council, see The Council page.

For more details about the panic system and management, see Managing Panic.

Continent Analysis

Besides choosing where to start, deciding the first continent to be covered with satellites is another major decision determining strategy. Some continents give strategic benefits right from the beginning while others might take more time to get dividends from them.

Country and Continent Bonuses per Month (Easy/Normal) Satellites Africa Asia Europe North America South America 1 +1 engineer +2 engineers +2 scientists +1 scientist

+1 engineer +1 scientist 2 +1 scientist

+2 engineers +3 engineers +3 scientists +2 scientists

+2 engineers +2 scientists

+2 engineers 3 +2 scientists

+3 engineers +6 engineers +6 scientists +4 scientists

+4 engineers 4 +8 engineers +8 scientists

Country and Continent Bonuses per Month (Classic/Impossible) Satellites Africa Asia Europe North America South America 1 +1 engineer +1 engineer +1 scientist +1 scientist +1 scientist 2 +1 scientist

+1 engineer +2 engineers +2 scientists +1 scientist

+1 engineer +1 scientist

+1 engineer 3 +1 scientist

+2 engineers +3 engineers +3 scientists +2 scientists

+1 engineer 4 +4 engineers +4 scientists

North America

Resources: §320, 4 Scientists & 2 Engineers (Classic and Impossible)

Bonus: Air & Space - All aircraft and aircraft weapons cost 50% less to purchase, build and maintain.

- All aircraft and aircraft weapons cost 50% less to purchase, build and maintain. One of the more useful bonuses in the middle game, being able to procure Firestorms for 50% off is incredibly useful, especially if you're down to the wire on materials. The 4 additional monthly scientists are also a nice addition to keep up with the increasing research times.

As a starting continent it will give you a total of §110 credits saved in March and April (§40 from purchasing 2 to cover the first continent covered + §70 from monthly maintenance, Skyranger included). This makes it somewhat useful as a starting bonus, if you're looking to build the 2nd Uplink in March or April and need to buy more Interceptors to cover it.

The high initial funding of the United States (which is given since it will be HQ's location) means that North America provides you with the highest initial monthly funding on Classic and Impossible (on Normal and Easy Africa wins due to higher base funding).





South America

Resources: §170, 2 Scientists & 1 Engineer (Classic and Impossible)

Bonus: We Have Ways - Interrogations and Autopsies are completed instantly.

- Interrogations and Autopsies are completed instantly. Can be really useful if it's your starting bonus or you can get it within the first two months, in order to pursue a Alien Base Rush strategy.

Otherwise, Interrogations and Autopsies don't take that long to begin with and if you collect scientists, they'll only take 1 or 2 days at most. Far more useful however if you're playing with Marathon on from Second Wave, since everything takes a little bit longer. Overall however, not a very pressing bonus to get, and it provides the least additional personnel of all resources.

On Impossible if you want to get to the Alien Base and complete the game before you encounter some of the more difficult aliens then this can help by unlocking Research Credits as well as the Alien Base once you get to the point of needing the Outsider Shard.

The Enemy Within DLC makes this bonus a more attractive due to autopsies granting access to Gene Mods and several more items. Researching laser weapons and Carapace Armor is also a little slower and they compete with Meld-related research, making early game research time more of a premium.





Europe

Resources: §430, 10 Scientists (Classic and Impossible)

Bonus: Expert Knowledge - Labs and Workshops cost 50% less to build and maintain.

- Labs and Workshops cost 50% less to build and maintain. As a starting bonus, unless you're pounding out Labs in the very early days of the game, or playing with Marathon turned on, Labs aren't that useful. If pursing a Satellite Rush strategy you may need a Workshop to build the 2nd Uplink, allowing a saving of §65 in March.

Each Lab/Workshop built costs less §65 credits, so if you're looking to build several of those, this is definitely a continent to look for posterior expansion. Furthermore, getting all of the European countries give the highest continent funding (§430) and the 10 monthly scientists it provides (on Classic/Impossible) will take care of all research needs.

On the Enemy Within DLC, the increased Research times and plasma weapon manufacturing costs in Classic/Impossible difficulties can also make Europe as an attracting option for expansion to deal with the bigger requirements.





Africa

Resources: §250 (§325 with 30% bonus), 3 Scientists & 3 Engineers (Classic and Impossible)

Bonus: All In - Monthly XCOM funding increased by 30%.

- Monthly XCOM funding increased by 30%. One of the most useful starting bonus. That extra money is going to pay dividends in both the long and short run, and the early and late parts of the game. You need credits for everything, and you can never have too much.

On the downside it gives few scientists and engineers so you'll need to get those from mission rewards. Keep in mind that extra engineers can be more useful than extra credits since they also allow for savings on advanced materials required for building stuff (Elerium, Alloys) later on.





Asia

Resources: §320, 10 Engineers (Classic and Impossible)

Bonus: Future Combat - All projects in The Foundry and the Officer Training School cost 50% less.

- All projects in The Foundry and the Officer Training School cost 50% less. Asia's bonus can be useful to start if you're not looking for a Satellite Rush strategy and prefer instead to build up your squad with OTS and Foundry upgrades.

Otherwise, if you're not focusing on those at start, the savings are quite limited on the beginning. But when you start to focus on your Foundry and OTS upgrades, you're going to wish you did have it. Especially the Foundry upgrades, since those compete for materials (Alien Alloys, Elerium, Weapon Fragments) alongside Research and Engineering. Completely covering the continent gives you +10 monthly additional engineers, which will also cut down the credit and resources cost of building new items.

The Enemy Within DLC has made this slightly more attractive in the early game. The Foundry grants adjacency bonus to workshops and the very valuable Tactical Rigging project makes an early Foundry more attractive than it was in the original game, and this bonus will allow you to capitalize on it more easily while money is still tight.



Africa Can Be Key

As strange as this sounds, because of game mechanics and because you need full satellite coverage as fast as possible (or at least 8 countries covered), the African bonus in credits is probably your most important reward, if you're starting to play the game or don't have a preset strategy. Alternatively you may consider North America as your first and cover Africa afterwards, but this strategy may not be viable since satellite launches are generally dependent on panic level.

Otherwise, if you're pursuing more advanced strategies, such as Alien Base Rush or Satellite Crawl, the other continents all have their uses.

Satellite Network

Plan ahead and cover the entire world with at least 8 satellites, regardless of your initial strategy. This is the only undisputed rule in playing this game, otherwise it may be impossible to keep enough countries in the Council to prevent losing the game.

It is more "economical" to panic management to launch satellites at the end of the month, to lower panic levels when they're highest, and to avoid an abduction mission invalidating the reduction. Launching satellites at the end of the month also gives you more flexibility to deal with unexpected alien activity at the end of the month.

Try to completely cover continents. Any countries covered at the start of the month (i.e., they're already covered when the Monthly Report comes in) will be off the list of Abduction Missions but will still get raised panic if another country on that continent gets an unanswered Abduction.

Order satellites individually, not in bulk. That way you'll be able to cancel satellite orders if you are in a dire/unexpected need of credits and still be able to launch the other satellites at the end of the month. Of all game items (Facilities, Craft, etc.) that require days for manufacture Satellites are the most flexible to cancel, if needed.

On the middle/late game always a backup satellite ready for launch. You may have to face a Battleship on a destroy satellite mission and be unable to shoot it down, which can lead into losing the satellite and quite possibly the country. Keeping a reserve satellite allows to launch it to replace the destroyed one and don't lose the country.





Budget & Funding

Credits and recovered alien artifacts are crucial to winning the game. The Situation Room allows to check your current budget (through the Finances tab) and to quickly raise cash by selling artifacts at the Grey Market. There are other ways of getting more resources such as completing missions.

For more details about the recovered alien items and their sell values, see the Alien Artifacts page.

For more info about what costs you credits and how to raise more credits, see the appropriate pages, Finances and Economy.

For details about mission rewards also see Council Mission Rewards





Grey Market Bonanza

The Grey Market is your best friend to quickly raise credits by selling alien artifacts.

For veteran players of the original X-Com that are new to this game, take heed that corpses and miscellaneous items are no longer useless junk. They are valuable resources used not only for Research projects, but as resources for completing Council member requests, Foundry upgrades and as components for manufacturing certain advanced equipment such as Chitin Plating.

Generally, keeping about 10 corpses of the common species (Sectoids, Thin Men...Mutons, later) in storage should be sufficient if you need some quick money. Keep more if you know you'll need them for a Foundry project.

On the other hand, items that have no research value such as damaged UFO components and Alien Entertainment are clearly marked as such. These items can be sold freely.

Once you are familiar with the game and know how much of each is required for tech that is within reasonable grasp, only then should you consider selling valuable equipment and corpses to fund whatever your strategy requires.

Usually items like UFO Flight Computers and Power Sources will only be required later when you start building Firestorms so those can be sold without consequences. However, you will need them later on, so plan on when you want to start upgrading your aerial fleet and start hoarding resources in advance for it.

Engineering

The Engineering section allows to access all aspects related to building items and base facilities, as well as S.H.I.V. construction and MEC Trooper augmentation (on the Enemy Within DLC).

For more details see the appropriate pages:

Manufacturing Tips

Most advanced items can only be built if you have enough engineers to fulfill their requirements. It's pointless to rush Research if you can't built the new toys and facilities afterwards.

The more engineers the less it will cost to produce any items, such as equipment, weapons, armor or craft. The savings are applied both in credits and in Alien Alloys and Elerium. The maximum gains occur with 3 times the number of engineers required, although the reduced cost will never go down below 50% of the original cost.

Workshops adjacent to one another give you a rebate in resources (§, Alloys and Elerium) used in projects such as Firestorms, Foundry projects and facilities, after they are completed. The rebate is of 7% (10% on Enemy Within DLC) for each adjacency, so 4 workshops in a 2x2 configuration will give you a 28% (40% on the Enemy Within DLC) in building costs.

However, there's a monthly maintenance cost of §26 for each workshop, so the improved efficiency comes at a price.

The North America continental bonus will reduce the costs of buying/building aircraft and their weapons by 50% and the Asian bonus does the same for Foundry projects and while buying S.H.I.V.s so you may want to consider getting those.

That's Resources Baby!

Winning the strategic game is about getting enough resources to purchase, build and research stuff.

There ain't no such thing as a free lunch [1] - credits (§) are required to hire soldiers/Interceptors or to build everything. And one of your main sources of § in the early game is the Grey Market, where you'll have to sell other resources (alien tech) to get the money you need, which may lead to shortages later.

[1] - credits (§) are required to hire soldiers/Interceptors or to build everything. And one of your main sources of § in the early game is the Grey Market, where you'll have to sell other resources (alien tech) to get the money you need, which may lead to shortages later. Manufactured items can only be sold through Council requests and those only come once or twice during the month, so it can be tough to get rid of obsolete items. More frequently the Council will request your more advanced weapons, which will put in the dilemma of fulfilling the request (and not having them for the next mission) or ignore it and don't get the § or scientists/engineers supplied by the country issuing the request.

Alien tech cannot be manufactured unlike the original X-COM, only captured. Items like Alien Alloys and UFO technology all have to be recovered from the battlefield.

Weapon Fragments and Elerium are usually the most scarce resources. The first on the middle to early game, since fragments are used also for research. Elerium shortages are quite common on the middle to late game, when you want to build the new items researched. UFO Flight Computers and UFO Power Sources are required for their research and for building Base Facilities like Elerium Generator and Satellite Nexus, as well as building Firestorms and the Foundry's Stealth Satellites. Selling too much of them at the Grey Market (where they have the highest prices) can also lead to shortage problems if you want to build projects that require them.

Alloys, Elerium and UFO Power Sources/Flight Computers are mainly recovered from UFOs, so if you're having problems shooting them down that can also lead to shortages. Equipping your craft with the EMP Cannon to shoot down UFOs will increase the probability of getting these items intact (instead of damaged and nearly useless) from 50% to 100%. You may get few amounts of both Elerium and Alloys from the dead bodies of some aliens like Heavy Floaters, Cyberdiscs, Sectopods and Drones though.

Meld, which is a new resource introduced by the Enemy Within DLC, is the scarcest resource since you'll only be able to regularly capture it on Abductions and UFO missions, along with the dead bodies of some aliens. Meld is only used on the Cybernetics or Genetics labs so its shortages won't be felt as bad as some of the other resources. You'll usually only get enough Meld during a game either field 2 MEC Troopers with the most advanced MEC Suit or to give 3 or more Gene Mods to all soldiers in your squad.

Assaulting the Alien Base will give you a ton of all resources from the mission salvage, which can be a real relief.

Fusion Cores can only be recovered from alien Battleships and they allow for Fusion Lance and Blaster Launcher research. If you're looking to get those on the middle/late game, just ignore an UFO and wait for the Battleship to appear. You'll need to shoot it down (otherwise it might destroy a satellite) and assault it afterwards though.

Alien bodies are more easy to come by but you'll require a few of them at specific times, such as Muton Corpse for getting the critical Foundry Ammo Conservation project and others. Sell them but always keep an eye on retaining enough corpses for these essential projects.

Foundry's Bag of Tricks

At some point during the game you'll need to build the Foundry in order to benefit for its projects. However, some are better than others, some are very specific and some will imply large amounts of resources to be constructed.

Very Useful

Ammo Conservation - Get it ASAP. Having the double of ammunition for your soldiers can really make a difference, specially during the middle/late game, where the larger aliens will require several shots to be killed.

- Get it ASAP. Having the double of ammunition for your soldiers can really make a difference, specially during the middle/late game, where the larger aliens will require several shots to be killed. Improved Medikit - Boosts the Medikit's base healing power by 50% and also improves a MEC with Restorative Mist. Your troops will appreciate it.

- Boosts the Medikit's base healing power by 50% and also improves a MEC with Restorative Mist. Your troops will appreciate it. Tactical Rigging (EW DLC) - Carrying two items allows for a lot more flexibility by bringing extra grenades, Medikits, S.C.O.P.E.s, armor, etc.

(EW DLC) - Carrying two items allows for a lot more flexibility by bringing extra grenades, Medikits, S.C.O.P.E.s, armor, etc. S.C.O.P.E. Upgrade - Even if you are only using S.C.O.P.E.s on your Snipers, get it for them.

Useful

Stealth Satellites - Retaliation UFOs will only be generate if you completely ignore landed or flying UFOs, so it can be easy to prevent the retaliation by simply launching an interceptor or the Skyranger and aborting the mission as soon as it starts. However, on Classic/Impossible difficulties, you'll face Battleships sooner in those retaliation missions so this project may be handy, specially if you are playing with the Second Wave's Diminishing Returns option.

- Retaliation UFOs will only be generate if you completely ignore landed or flying UFOs, so it can be easy to prevent the retaliation by simply launching an interceptor or the Skyranger and aborting the mission as soon as it starts. However, on Classic/Impossible difficulties, you'll face Battleships sooner in those retaliation missions so this project may be handy, specially if you are playing with the Second Wave's Diminishing Returns option. Improved Arc Thrower - Get it if you are planning for capturing aliens to get their weapons or Research Credits from interrogating them, otherwise don't bother with it.

- Get it if you are planning for capturing aliens to get their weapons or Research Credits from interrogating them, otherwise don't bother with it. Advanced Repair - Useful for S.H.I.V.s (if you are using them) but not worthwhile for aircraft. Since the game is set for a maximum of 2 regular UFO missions per month (and they usually happen in different continents) the increased repair time becomes irrelevant and a waste of resources.

- Useful for S.H.I.V.s (if you are using them) but not worthwhile for aircraft. Since the game is set for a maximum of 2 regular UFO missions per month (and they usually happen in different continents) the increased repair time becomes irrelevant and a waste of resources. Advanced Flight - Interesting for Archangel Armor and Hover S.H.I.V.s but it is very expensive to complete. Plus, if you only use Archangel on Squadsight Snipers then they really don't need the extra flight time if you place them correctly on the battlefield.

- Interesting for Archangel Armor and Hover S.H.I.V.s but it is very expensive to complete. Plus, if you only use Archangel on Squadsight Snipers then they really don't need the extra flight time if you place them correctly on the battlefield. Improved Pistol I & III - Interesting if you use a lot of pistols, don't spend resources if you don't.

- Interesting if you use a lot of pistols, don't spend resources if you don't. Alien Grenades - Useful if you are playing the Enemy Within DLC, otherwise don't bother.

Don't Bother

Advanced Construction - If this become available at the beginning of the game it would be very useful but by the late game (when Sectopods usually appear) its only use (besides spending resources) is to rush the Gollop Chamber, but there's usually no need to do so.

- If this become available at the beginning of the game it would be very useful but by the late game (when Sectopods usually appear) its only use (besides spending resources) is to rush the Gollop Chamber, but there's usually no need to do so. Improved Pistol II - Currently bugged.

- Currently bugged. Drone Capture - Will depend a lot on the tactical situation to be useful and it is expensive.

S.H.I.V. and MEC Projects

All projects related to these 2 units are very useful (and expensive) - if you're using them, plan on getting some or all. If you're not using S.H.I.V. or MECs don't bother with any of them.

Research

Research is the key to victory since it allows you to keep up with the escalating tech levels of the aliens. The Research section also allows to apply Gene Mods for your soldiers, on the Enemy Within DLC.

For a description of all research projects and their requirements, as well as tech trees, see Research.

For details and tips about soldier genetic modifications, see Genetics Lab & Gene Mods.





Research Tips

Research Paths

Speeding Research

Consider refraining from building laboratories, unless you're playing the EW DLC. They aren't really necessary even on higher difficulty settings since they don't provide additional scientists (you'll need to get them from rewards or by covering countries/continents with satellites.

You can still complete research quickly by first researching Xeno-Biology and the Arc Thrower, building the Alien Containment and following up by completing all autopsies and interrogations. Completing both projects and capturing and interrogating live aliens give Research Credits which can cut the research time of some projects by 50%. As a bonus you'll also capture intact the alien's weapons, which can be used later by your soldiers after they're researched. The South America continental bonus really shines when combined with captures/interrogations, since the research time for interrogations is immediate, allowing you for major research breakthroughs. Later, the Muton Elite and Ethereal interrogations give a 25% reduction in all weapons and all tech research and both stack together, so consider capturing both species during the Overseer mission.

It is possible to skip Laser research completely by capturing intact a Light Plasma Rifle and researching it. Specially if you get the Research Credit of capturing and interrogating a live Muton, which cuts research on all plasma weapons by 50%. It is also possible to skip Light Plasma Rifle research and got for the better Plasma Rifle if you capture one of those intact.

Besides the duration of some research, the biggest obstacle to research is the required alien artifacts that are gathered slowly, specially Weapon Fragments. Building laboratories only serves to drain these precious resources.

However, if getting gear for your troops is an urgency for your play style, 1 lab early on may be appreciable, especially if your mission rewards or satellite coverage don't gain you any scientists whatsoever.

If playing the EW DLC, labs will be more useful due to the longer research times in Classic and Impossible difficulties. They also help against EXALT's research hacks, which will slower your research.

Hangar

The Hangar concerns equipping and deploying Interceptors/Firestorms to engage and shoot down any UFOs that appear on Earth's skies. For more details see the appropriate pages:





Barracks

The Barracks is where you'll manage all essential aspects related to your soldiers, namely hiring, equipping and promoting them, as well as purchasing squad upgrades through the Officer Training School, psionically training soldiers, and in the Enemy Within DLC assigning them medals. For more details see:

General Tips

Rotate lower ranked soldiers to use as "cannon fodder" while leveling up your higher ranks. Once your higher rank has reached the highest, leave him in base and continue to level up more promising ones. Don't bother hiring new soldiers unless they're needed.

This all changes after you purchase Iron Will and New Guy in the OTS. At this point, you should have enough credits to hire soldiers by the bundle, and sack the low Will ones. Your core team of high ranking officers are now your "cannon fodder" while you level up the new Squaddies. You may also consider Psi screening them before choosing which new recruits to keep and promote.'

and in the OTS. At this point, you should have enough credits to hire soldiers by the bundle, and sack the low Will ones. Your core team of high ranking officers are now your "cannon fodder" while you level up the new Squaddies. You may also consider Psi screening them before choosing which new recruits to keep and promote.' Enlarging the pool of soldiers helps with dealing with possible "Code Black" scenarios, where all soldiers are lost during a mission. Such squad wipes are common to happen and it is possible to recover from them.

Getting the OTS is a major requirement since many upgrades will bring faster promotions and better stat gains, as well as enlarging the number of soldiers possible during a mission, increasing the possible slots for soldiers in training.

Getting a Sergeant is required to unlock Squad Size I (which you should get right away, as well as Squad Size II to increase your squad) and, on Classic/Impossible difficulty levels to allow construction of the OTS. A Sergeant also unlocks Wet Work which gives a 25% boost to experience points gained through killing, making it very useful for training. It can be gained either through focusing on promoting a single soldier to that rank, usually a Sniper with Squadsight since they're less likely to suffer injuries and they usually amass a lot of kills. Alternatively, a Sergeant may also be gained as a reward from a successful Abduction/Council mission.

(which you should get right away, as well as to increase your squad) and, on Classic/Impossible difficulty levels to allow construction of the OTS. A Sergeant also unlocks which gives a 25% boost to experience points gained through killing, making it very useful for training. Usually the distribution of classes will not be balanced, although the class assignment has been improved on the Enemy Within DLC. But you can also use rewards to make up with any shortfalls or to get immediately replacements for high rank officers lost during missions.

On the Enemy Within DLC, use medals to make up for any low Will stats of your soldiers.

Promotion Suggestions

If you have no idea of what Abilities to choose during the first promotions, these are solid choices for the entire game:

Assault - Lightning Reflexes . Forces a miss on the first reaction shot fired at the unit. Can be used to trigger (and miss) alien Overwatch shots. This ability is essentially a life-saver for your soldiers when advancing against aliens on Overwatch, specially Sectopods.

. Forces a miss on the first reaction shot fired at the unit. Can be used to trigger (and miss) alien Overwatch shots. This ability is essentially a life-saver for your soldiers when advancing against aliens on Overwatch, specially Sectopods. Heavy - HEAT Ammo . After you first encounter a Cyberdisc without this ability, you'll know why. It also applies to the Rocket/Blaster Launcher, and grenades, and the Volunteer's Rift ability, besides the Heavy's primary weapon and you are almost sure to face Cyberdiscs/Sectopods on most UFO or Abduction/Terror missions.

. After you first encounter a Cyberdisc without this ability, you'll know why. It also applies to the Rocket/Blaster Launcher, and grenades, and the Volunteer's ability, besides the Heavy's primary weapon and you are almost sure to face Cyberdiscs/Sectopods on most UFO or Abduction/Terror missions. Sniper - Squad Sight . Snap Shot also has its uses but it requires Squad Sight to perform the classic 'Scout and Snipe' tactic of the original game, where your Sniper can just pick a spot where it covers the battlefield and drop any aliens seen by your squad.

. Snap Shot also has its uses but it requires Squad Sight to perform the classic 'Scout and Snipe' tactic of the original game, where your Sniper can just pick a spot where it covers the battlefield and drop any aliens seen by your squad. Support - Field Medic . Never go to a battle without a Medikit. And never risk your only Medic getting killed or worse, critically wounded (and watch him/her die from the wound unless you are able to finish the fight first).

. Never go to a battle without a Medikit. And never risk your only Medic getting killed or worse, critically wounded (and watch him/her die from the wound unless you are able to finish the fight first). MEC Trooper - the first soldier augmented should be a Heavy due to its starting Body Shield ability or even an Assault with its Shock-Absorbent Armor ability. This because a MEC will be a bullet sponge and the more time you can keep it alive the better. Later, Sniper turned MECs are also very powerful but you'll need to convert them at Colonel levels to let their Aim stat to grow as much as possible before conversion.

Soldier Progression

Early Game

The initial missions can be used to reveal the class of the starting soldiers or to increase the experience points (XPs) of the survivors of the first mission to maximize their progression in the ranks, or both. The first need is required if you want to start enlarging the pool of trained soldiers. But it disappears after the New Guy OTS perk is purchased, since the class of all existing or newly hired rookies is immediately revealed. Choosing instead to favor promotions allows quickly to get critical abilities like Squad Sight for Snipers and to unlock OTS upgrades. On the Enemy Within DLC, the promotion XP requirements have been increased, which favors the promotions first approach.



Middle/Late Game

Later, the emphasis usually switches to building a pool of soldiers usually around 10-12 soldiers, with around 6 preferred class builds, plus replacements for injuries and KIAs.

Another important issue is to replace soldiers with low Will stats since the original soldiers will be more likely to suffer critical wounds and not benefit from the Iron Will OTS upgrade. If using the Not Created Equally Second Wave option, it may also be worthwhile to use it to hire large batches of Squaddies and only train the ones with the best stats.

OTS upgrade. A basic setup is to have 2-3 soldiers of each class, depending on personal preferences - your favorite build(s) for that class and his/her replacement, its also possible to have an alternative build for more specialized missions.

Always bringing at least 1 soldier for training during missions is very helpful, in order to develop further the pool of soldiers. Some missions are better for bringing several low ranked soldiers, like Council missions after you've deployed Titan Armor, or even Abductions and/or Small Scout UFO missions. Other missions, like Terror Sites, the Alien Base or large UFOs can be more challenging for soldiers in training but also more rewarding since the trainee will have the possibility to earn more experience points through killing larger aliens.

After the Psi Lab is built the emphasis changes to checking the pool for Psionic soldiers and training them.

Mission Control

Mission Control is where you order the game's time to advance and watch as events unfold and missions are generated. As days and months go by you'll be presented with a choice of combat that will affect the overall situation, regardless of being chosen or ignored, or being a victory or a failure. Missions are also the major source of resources such as Weapon Fragments/Elerium/Alloys/Meld to be researched, sold or used at Engineering.

Regardless of all your preparations, winning missions is the key of achieving victory over the alien forces. The whole tactical aspect will be deal in the separate page Tactics due to its complexity. This section will deal exclusively with the strategic impact of missions throughout the game.

For more specific details about this topic see:

Timeline Progression

The game is designed to introduce new enemy units (both Aliens and EXALT) and UFOs at specific months, regardless of the difficulty level. The frequency of missions (Abductions, Terror Sites, UFOs and Council) is also scripted according to the current game month and the Storyline progression.

Second Wave's Marathon option delays the introduction of new alien species and UFOs but retains the frequency of the missions.

Mission Frequency

Abductions - 2 rounds possible each month, if there are 5 or more countries without satellites. Each round of abductions require a minimum of 2 countries to happen, with a maximum of 3 on each round of abductions. Once a country is targeted for abductions it won't be targeted again on the same month. After the Alien Base assault, Abductions can still happen if there's 2 or more Council countries without satellites. If there are still 6 countries without sats it is possible for the game to randomly choose a 2nd round of Abductions.

Terror Missions - every 2 months Assaulting the base changes it to a Terror Site each month.

Flying/Landed UFOs - 2 possible each month If the Alien Base isn't assaulted, the frequency of UFO appearances is reduced to a single alien craft each month in June and afterwards. However, if the 2nd round of Abductions hasn't been added due a lack of available countries, the game will automatically add a 2nd UFO. After the alien base is assaulted, it is possible (50% chance) to get a 2nd UFO every month.

Council missions - 1 monthly mission between the 15th and 27th (unless the Tutorial is activated). If Slingshot is activated, Friends in Low Places is the first Council mission, followed by Confounding Light and Gangplank. The 3 missions can be postponed indefinitely by ignoring them since they will keep reappearing until you've taken them. On the Enemy Within DLC, between 0 or 1 monthly Council missions possible. The Slingshot campaign or Progeny's Portent missions complement the regular Council missions, if they're activated. It is possible to have a Council mission and another from either campaign on the same month. If both are activated, Portent takes place before Friends In Low Places. It isn't possible to ignore any of Slingshot or Progeny missions on the Enemy Within DLC. Once ignored the mission will never return and the campaign will be aborted. Site Recon will be the 1st Council mission generated after the 1st Terror Site. Afterwards it joins the pool of possible missions.

Base Defense - 2 to 3 weeks after XCOM assaults the Alien Base (EW DLC)

Progeny campaign Deluge and Furies missions - after Base Defense.





Storyline Progression

Alien Base Assault

The Alien Base Assault is the most decisive Storyline moment affecting the overall strategy, due to its effect on the game:

If successful, it will give a worldwide panic reduction, a big chunk of loot for sale at the Grey Market and a boost of your squad's experience, all of which can help the overall situation in the early game.

However, after the Alien Base all UFO missions will now have Sectoid Commanders instead of Outsiders as their commanders, making it harder to assault UFOs and recover alien artifacts.

The longer you wait, the better equipped XCOM will be for the mission but the base alien garrison will also deploy the latest alien species.

Researching the artifacts found there will unlock Ghost Armor and psionics.

On the EW DLC, the XCOM Base Defense mission will take place 2-3 weeks after the Alien Base assault, where you'll face a massive horde of the most advanced aliens in defending HQ or lose the game.

After the assault, Terror missions will happen each month, instead of only in the even months.





Overseer UFO

Building the Hyperwave Relay triggers the appearance of the Overseer UFO, over any continent that has satellites deployed. Check Air Combat for the requirements to shoot down the Overseer.

The Ethereal will first appear while assaulting the crashed Overseer UFO, but on the EW DLC it can appear before, during the XCOM Base Defense mission, depending how long it took you to assault the Alien Base.

The Overseer assault will also see the first appearance of Sectopods, if they haven't appeared on regular missions before.

After the Overseer mission all UFO missions will now have Ethereals (with Muton Elites as escorts) instead of Sectoid Commanders as their commanders, making it harder to assault UFOs and recover alien artifacts.





Temple Ship Assault

Once you've retrieved and researched the Ethereal Device from the Assault the Overseer mission, built the Gollop Chamber and equipped a Psionic soldier with Psi Armor you'll be given the chance of taking the last mission. Remember that you'll need to finish the Gollop chamber first then re-equip the Psionic soldier with the Psi armor, otherwise you'll get the message that there's no soldier capable of using the Ethereal Device.

The soldier that used the Device will be turned into the Volunteer and will possess a special Psionic ability called Rift . Any Psionic soldier can be the Volunteer, regardless of its current psi rank - he/she will be promoted to the top psi rank after using the Device and you'll be able to choose between psionic abilities like in a normal promotion.

. Any Psionic soldier can be the Volunteer, regardless of its current psi rank - he/she will be promoted to the top psi rank after using the Device and you'll be able to choose between psionic abilities like in a normal promotion. After you've used the Device all of your research projects will be frozen and you won't be able to conduct any more missions to retrieve alien artifacts or get promotions for your soldiers. You'll still be able to build items on Engineering though.

If you'll complete this mission you'll have won the game (but you can repeat it if you lose it). Congratulations :)

Now try playing the game again at a higher difficulty level.





Mission Choices

You will be considering several things when deciding on which mission to choose or ignore, specially regarding Abductions. However your considerations should come in these orders:

Panic Levels

Your choice differs vastly depending on difficulty level and mission type. For example, on easier difficulty settings, ignoring some missions can lead to increased panic for one country. In comparison, this could lead to increased panic in the whole continent on higher difficulty settings or in some specific Council missions. Thus, consider panic level on the whole rather than individual countries. In some cases, continents with more countries should be taken care of first.

In Abductions, if you are offered more than one country from the same continent to chose from, choosing one of the countries on the continent will mean that this country gets panic decrease and other countries from same continent get no change in panic levels. Leaving more than one country on same continent unattended will not multiply continent-wide panic (eg., on Classic ignoring China and Japan will raise panic in those countries by 2 and in other Asian countries by 1. It might be worth ignoring South American abduction missions. An unanswered abduction on that continent raises total panic by 3 points (2+1) while an unanswered one in Europe or Asia gives 5 panic points (2+1+1+1).

Terror Sites will always cause the country to leave XCOM if the mission is ignored or a failure, so keep that in mind.

Regarding UFOs, you should always launch an Interceptor if they're detected flying, even if to abort the engagement before any shots are fired. Any ignored UFOs (flying or landed) increase panic over the country by 2 points and will cause a 2nd UFO to appear and try to shoot down the satellite, while escaped UFOs will only increase panic by 1 point and no retaliation UFO will be generated. Crashed UFOs remove panic by 1 point and can be ignored afterwards with no panic increase.

Council missions depend on the specific mission. Some will raise panic only in the country, others in the whole continent, and a few will not raise any panic at all. The same applies for panic reduction from these missions.

Successfully assaulting the Alien Base will give a worldwide reduction of panic by either 1 or 2 points, depending in the difficulty level, which gives it a major strategic effect.

On the Enemy Within DLC, anti-EXALT missions (a.k.a. Covert Operations) will always reduce panic by one point, if successful. If ignored, the cell will hide and redeploy itself to perform further anti-XCOM missions, which can raise panic. Assaulting the EXALT Base will also give a worldwide panic reduction.





Difficulty

Missions at the beginning of each month are the most dangerous since usually new aliens will be introduced, as described on the previous table.

Council and EXALT missions can be some of the hardest during the early months, specially the Bomb Disposal ones. However, after you start upgrading to Lasers/Carapace and get the Squad Size upgrades, they'll be more easy and ideal to train rookies.

Terror Sites and Large UFOs will always contain the biggest (and more dangerous) aliens such as Cyberdiscs, Berserkers and Sectopods so keep an eye for those.

The Slingshot and Progeny campaigns can be very brutal when first played but after you've learned the locations of the scripted appearances of aliens their difficulty is reduced.

Abductions depend a lot on the map. Some maps are specially dangerous on Abduction missions, due to their openness, small size and/or general lack of full cover. However, you won't know which map you'll get until the Skyranger lands and it's too late to change anything.

Abductions will also be rated by their difficulty level, which is dependent on the number of aliens present during the mission.

Storyline missions are usually the hardest ones of the entire game.





Rewards/Salvage

Depending on the difficulty level and if playing the Enemy Within DLC, all choices can be important when deciding which country to help during Abductions. In order to have full satellite coverage, credits and engineers should be your preference. If full coverage isn't important, you will probably prefer engineers until you no longer need more for buildings or tech. Soldiers can be critical to unlock the OTS or replace KIAs. Scientists can be useful to speed up research.

UFO missions allow you the chance to recover big amounts of alien artifacts, which are required to research and build all of the advanced projects. Intact craft will give more resources, but they'll also have more aliens.

Council mission rewards depend on the specific mission. Overall, the rewards are always useful but you can't count on getting what you specifically need at the moment. Some Council missions can also be very hazardous, specially in the early game.

The loot from the Alien Base mission can be critical if you're running low on alien salvage.

Slingshot and Progeny will provide major rewards if the missions on their campaigns are completed.





Game Progression

As the game's timeline advances, certain decisions will be required in order to be able to achieve your goals. This is a summary of the major decisions that need to be taken at certain periods of the game, according to your overall strategy.

Early Game (March - May)

During the first months there are several needs that need to be addressed:

Keeping panic under control. Building up your squad to win key missions. Advancing your research to avoid being outgunned by the alien's escalating tech levels. Securing credits and personnel to build key items and facilities.

Later, after you've kept panic in control, the focus turns towards progressing through the Storyline. Most strategies deal mainly with the first months, since those are largely considered to be the most decisive of the game.

This period has several key events initially taking place:

The starting mission, either the Tutorial or an Abduction mission. Maps with better cover and elevations are usually easier than more open maps.

The 2nd Abduction mission. On the Classic and Impossible difficulties, this mission is usually harder than the 1st mission, due to larger number of aliens.

The Small Scout on the 1st UFO mission. If it is deliberately ignored a Large Scout will appear afterwards with a Destroy Satellite mission but, if shot down it will bring more salvage than the Small Scout.

The 1st Council mission. The entry of Thin Men with their exceptional mobility, aim and poisonous attack. Bomb Disposal missions can be literally impossible to win and dependent on extreme luck. If activated, the first missions of the Progeny and Slingshot campaigns take place instead.

The 1st Terror mission (April). Chryssalids and Zombies will appear for the 1st time.

The appearance of Mutons (with Light Plasma Rifles) and EXALT in May.

The flyover of the 1st Abductor in May.

There are at least 4 main strategies to reach the game's objectives while navigating through the early months: Satellite Rush, Alien Base Rush, Panic Control and Satellite Crawl. Check below for details on them.

Mid Game (June - August)

After surviving the initial months and with panic under control, the choices of the mid game are usually to attack the Alien Base (if it hasn't been done before) and shoot down and assault the Overseer UFO and capture the Ethereal Device during this period.

The main factor that determines the speed of the mid game are Research times for advanced weapons and armor and/or and having enough credits, Weapon Fragments, Alien Alloys, Elerium or Meld to build whatever is required in Engineering. The regular highlights of this period are:

The large appearances of Mutons (with Plasma Rifles) and Cyberdiscs in June.

The first appearance of Berserkers in July, on all types of missions except Council ones. EXALT Elites will also appear during this period.

The first appearance of Heavy Floaters in August.

The Abductor and Supply Barge UFOs appearing regularly, with Landed Abductors in June and Supply Barges in the months afterwards.

The main points to look for are:

To keep an eye on the Doom Tracker and prevent an accidental loss of a country (and possibly the game) through a failed Terror Site or a Battleship shooting down a satellite.

To develop plasma weapons and armor (Titan onwards) to deal with the more armored alien units that start appearing.

To complete the necessary Foundry and OTS projects.

To develop and deploy Plasma Cannons and the Firestorm to shoot down the larger UFOs.

To secure enough alien resources (Alloys, Elerium, etc.) to build/research all of the previous.

Usually, this is a stage where a player may want to build Workshops and Laboratories to help on the way.

Late Game (September onwards)

The main objectives are still those of the previous game stage, with the addition of conducting the final mission (Temple Ship Assault). The duration of this period will depend on the player's choice on how much further it wants to keep playing before taking the Storyline missions. It is possible to choose not to build the Alien Containment and capture the 1st alien or assault the Alien Base until September or even later.

The main changes are the introduction of Sectopods, Muton Elites and Battleships in September. It is also common for the EXALT Base Raid to take place in September due to the number of clues required to detect the country that is harboring their HQ.

Specific Strategies

Satellite Rush

Satellite Rush deals with panic by aiming to build a 2nd Satellite Uplink on March, along with 4 satellites, and later to construct at least 1 more Uplink on April, in order to get 8 countries covered by satellites and strongly reduce the possibility of them leaving the Council. Later, the player may choose to get a 4th Uplink to cover 4 more nations with satellites or control panic through other means.

Since panic control will be achieved through satellite deployment, the criteria to choose between Abduction missions is usually to go for engineers (to reduce satellite construction costs) or credits (to pay for satellites and Interceptors to defend them, Workshops and Uplinks). This strategy can work better with a North America or Africa start. North America reduces interceptor cost and Africa increases further the income received from satellite deployment.

More details: Satellite Rush Strategy

Alien Base Rush

With this strategy the focus is on research to assault the Alien Base on April for the worldwide panic reduction that takes place afterwards. The main milestones to achieve this are:

The building of the Alien Containment facility and the Arc Thrower to capture the 1st alien and the Outsider

Getting 10 extra engineers (for a total of 15) in order to be able to build the Skeleton Key to unlock the Alien Base Assault.

Optional research includes developing Laser weapons and Carapace armor to help during the assault, as well as OTS and Foundry updates.

The choice between Abduction rewards is to go either for engineers (to reach the minimum to build the Skeleton Key) or scientists (to speed up key research). A South America start is usually the best one since the We Have Ways bonus (immediate interrogations/autopsies) and early construction of the Alien Containment + Arc Thrower allows you to quickly complete key research steps. Other possible continents are Europe, to build Laboratories/Workshops in order to speed research or get the required engineers, or Asia to pay for the OTS/Foundry upgrades to equip the squad for the base assault.

More details: original post at 2K forums

Panic Control

This strategy can either be used from the start or as back up plan in case something went wrong with the 2 previous strategies. During the first 2/3 months the main steps to control panic are:

To choose the Abduction missions according to the country/continent panic situation and not the rewards.

Disregard the continental bonuses when launching satellites in order to prevent countries with a level 5 panic from leaving.

With this strategy, at the beginning of May you'll have 5/6 countries that left the Council and usually it will be required at that point that you build additional Uplinks or to assault the Alien Base to prevent losing the game due to more defections. The risk with this strategy is that to lose a single Abductions or Terror Site can have catastrophic effects, so you need to keep a decent squad prepared for all missions.

Due to the limited choice on Abduction rewards, the emphasis should be to maximize the use of what is given: scientists speed up research, engineers lower build costs and certain numbers are required to build some items, soldiers can unlock OTS upgrades be replacements for casualties, and credits are most welcome since you won't be receiving much of those through funding. This strategy can be applied from all continents, but Asia is usually the best since it reduces the cost of squad upgrades.

More details: Flexible Strategy (Impossible/Ironman) - original post at 2K Forums

Satellite Crawl

Other Specialized Strategies

Articles

Why South America Still Sucks - [original post at the 2K forums]