What is an exploit?

In a multiplayer game, how easy is it for other players to counter and defeat the exploit? If the only reasonable counter is for other players to use the same exploit, or extremely complex and specific strategies, it becomes a high priority for us to fix.





If the only reasonable counter is for other players to use the same exploit, or extremely complex and specific strategies, it becomes a high priority for us to fix. In a single player game, does it make the game trivially easy? When we design games, we have an idea of the level of challenge the game should provide at various points in the game’s flow. If an exploit allows a player to bypass or destroy that challenge, then we should try and fix it.

Critical Chance Stacking Exploit

Area Status Effect Spreading

The Unkillable Engulfer

Cheesing Enterable Structures

Honorable Mentions

Power leveling heroes by letting them solo armies alone, giving them huge XP gains (fixed in one of the Stegosaurus updates, I believe)





Kir’ko heroes being unkillable (again) by stacking Max HP mods and skills on them, and then giving them recover XXX% of max health per turn effects (fixed by making regeneration heal a fixed amount, rather than a percentage)

In a game as big and complex as Planetfall, exploits are inevitable. It’s almost impossible for developers to foresee all of the different ways that gameplay systems can interact with each other, and deal with all the issues that can arise from some of the weirder combinations. In this Dev Diary I thought it would be fun to talk about some of the exploits we’ve found through development, and how we’ve fixed them. Some of these exploits were in the Tyrannosaurus update, and were fixed in a patch we released today!This one’s gone though. We think. We can’t actually remember how it happenedI’m sure there are many different definitions out there, but when I talk about an exploit what I mean is:“A way for a player to manipulate the system to achieve a result that is beyond what the system is supposed to permit”This means part of the definition of exploit is subjective, when a player does something, I need to look at that say “Is that reasonable? Or is that so far beyond the rest of the system that it in some breaks the game”. There are a few ways of judging this, but the biggest ones are:You may note that I’m saying that multiplayer exploits are more important than single player ones (though obviously there’s a lot of overlap here). The main reason is that in multiplayer, the huge majority plays to win and will use any advantage they can get to do so. If an exploit guarantees a win, players will use it, and their opponents will either get angry and stop playing, or they will feel forced to use the exploit themselves, shifting the entire Meta into a very boring one-dimensional shape.In single player, the desire to compete is lower, and to a degree exploits can add to the game since players enjoy finding and making use of them. This means that we will occasionally not fix single player exploits since they are not viable in multiplayer, and we judge that players will enjoy the game more if the exploit is present.In the base release of Planetfall, the game did a critical hit check before it did a to-hit check. If an attack did a critical, then the hit roll could be ignored, and all attacks would hit. There were a few reasons behind this, but the main one was to make critical hit chance a more interesting and valuable stat for players. In this we succeeded very well indeed!The problem started with this guy:The humble Vorpal Sniper, a unit who many of us (pre-release) had viewed as a fairly run of the mill support unit that could do some damage if you got lucky. The main issue here is the “Power Shot” modifier, which grants 20% criticial hit chance. On its own, this isn’t immensely strong, but what if we were to add some mods?We’re at 30% now!And 40%.Oh look, we met the Paragons:Aaand, that’s 50%! For those keeping track, the mods have pushed our base damage to 26 by this point, so a crit does 39 damage.What if we’re really happy too? +600 morale is another 20% crit chance, so now we’re at 70%.Also, this same rifle is available as a Hero Iterm, and what can heroes learn?And this 5% stacks 3 times, so we can have a hero with a 85% critical hit chance! The strength of this was so high, that players going Assembly/Synthesis/Sniper Loadout could clear almost any site on the map with their starting army and a few mods (2 of the mods listed above are tier 1 research), usually not taking any damage in return.The core issue here was that critical hit effectively bypassed to-hit roles, meaning there was no real counter to this strategy. It didn’t matter if the unit was in cover, or a smoke screen, or a defense mode, it was going to get hit and take a horrible amount of damage in the process.This issue was resolved in the Ankylosaurus update, the game’s code was changed to clamp critical chance to hit chance, meaning if you had 90% critical chance but only a 10% chance to hit, the system would only give you a 10% chance to crit instead.Note that Ruthless Killer also needed to be nerfed here, since heroes would often kill with a crit on a sniper rifle and then immediately be able to fire again. By reducing the returned AP to 1, they would no longer be able to fire their sniper rifles twice in one turn.Finally, at the same time, the poor old Vorpal Sniper was nerfed as well, with it’s damage reduced to 18 and crit chance to 15%. This turned out to be insufficient, and a later patch reduced it’s damage further to 16.As one last note, many people complained about the Vorpal nerf, because while the unit was (and still is to a degree) an absolute monster when used by a skilled player, it does not do well in auto combat, so a lot of multi-player players felt a weak unit had been made even more useless. One of the biggest issues of balancing a game like Planetfall is trying to limit these kinds of side effects, where changes vital to one game mode have a negative impact on other game modes.This next exploit is, by chance, also one which happened to be very useful to Vorpal Snipers, and relates to this mod:The main issue with this mod is that the Area of Effect doesn’t just spread damage, it also spreads any special status effects that are attached to the attack as well. So, if you place this on a Vorpal Sniper, and use concussive shot:AoE crowd control! Now, on its own this isn’t a game breaking exploit, counters do exist for this, however it is clearly far too strong and allows low level units to bunch far too high above their weight. Also, we need to consider what happens when it’s applied to higher tier units:Anything getting hit by this is probably not going to be doing much next turn!Anyways, in the Tyrannosaurus update this mod has been changed so that extra effects no longer trigger within the extended area of effect. To make up for the nerf, we did increase the damage in the AoE to 75%.You can still make the above unit though, just put Fireburst Ammunition and Shockwave Infusers on an Assembly Wrecking Ship!This exploit is different for a number of reasons, firstly it’s still in the game (well, it was, we fixed it today) and secondly it’s not caused by one single issue, but rather by combining a number of things together. Each of these things alone is reasonable, but when combined in a certain way you get a perfect storm of unstoppable insect death.This is where we start, unmodded the unit is not particularly impressive (though it is definitely one of the stronger fliers), but once we stack shields, things tend to get a bit out of hand.This gives us +1 shield, and an ability that lets us get another +6 shields on ourselves an adjacent units (assuming we have 3 essence charges).The ability above stacks with Swarm Shields.This operation boosts swarm shield further.Don’t forget, this is a vehicle, so it be put on a hero, and that hero can learn this skill:That hero can also learn Guiding Aura, which is an area of effect Psionic Buff:This lets us use this mod:That’s another 3!Finally, since going all shields is boring, one last mod:Also, as a pièce de résistance, the Transfer Pain operation can be used on the engulfer, giving it another 35% damage reduction. Happily, Transfer Pain is also a Psionic Buff, so it can be used to reapply Mantra of Life too!This is what we, in game designer terms, call an “I Win Button” (this screenshot is from a Beta Tester, I’m not entirely sure how he got 1 more shield than me, probably some construction bonus from a sector upgrade)Now, this wouldn’t be so bad if not for the fact that the Engulfer isn’t really a slouch offensively either. Since if you can get it to gold rank:You get +1 range, this will stack with the +2 range from Guiding Aura, to give the Engulfer a range 10 attack! This means that even if your enemy has something that can bypass shields (such as a Ramjet) the chances are it’s not going to be able to live long enough to get into range anyways.The Amazon Lightbringer is also not really an option, since another Psionic mod (Path of Fire) allows a psionic buff to give an extra +4 thermal resistance as well, nullifying the lightbringers attacks!Finally, shield breaking effects are also not much use, since most of the shields here are temporary, so the “damaged shields” effect is lost when the shields get re-applied.Now we had already made an attempt to fix this in the Tyrannosaurus Update, various changes were made (Echo of Hivemind used to give 2 shields, for example) and released but this wasn’t enough, and in the next hotfix we are taking more drastic action. The main difficulty here is that none of the parts in this system are really too strong on their own, if we nerf them too much, we’ll make them useless to normal players. We already tested changing the range and base hit points of the engulfer during testing, and had to revert it because the unit became useless to normal players.In the end, we asked the fans and the beta testers, and combined all the ideas that felt reasonable into something that we hope will work. The final patch notes for the fix are:Hopefully this bug is squashed for good! (I’m 40, I’m allowed to make this kind of joke)Up until now, the exploits that we’ve seen have been to do with clever interactions between multiple combat mechanics. This exploit is much more straightforward, and much closer to the exploits that traditionally exist in many games, since it involves taking advantage of a loophole in a fairly straightforward rule. The loophole in this case, is that you do not need any move points to enter a structure and fight the units inside it.In Planetfall, players can enter battle, shoot off some abilities, and then run away before the enemy can respond. When they retreat, their units have all of their move points stripped, so they cannot immediately re-enter battle and do that again in the same turn. This restriction doesn’t work on Enterable structures however, and we’ve had reports of players clearing max level landmarks on turn 6 by repeatedly doing the same combat 18 times in one turn (usually, they have units with once per battle heal abilities they can use to keep their units from dying.)This type of exploit is not an issue in standard multiplayer or singleplayer, however in PBEM games, where players have a lot of time to optimize their turns as much as possible, it can be a serious issue. If a player is doing this, they can get a huge advantage by clearing end game structures early, and the only counter is for the player’s opponents to do the same thing. Since obviously this is quite a tedious and unfun process, it can ruin games for people and needs to be fixed.This has gone on for long enough, so a quick call out to the exploits I left out:Anyways, I hope you’ve enjoyed this Dev Diary, and are continuing to enjoy the game! We’ve finished development on the Tyrannosaurs Patch, but we’re still working on the next expansion and it too will come with another free game update. It won’t be as big as the Tyrannosaurus Update, but hopefully we’ll have some nice things in it for you all!