Killing Floor 2 from Tripwire Interactive is a first-person shooter (FPS) with a sci-fi horror theme in which teams of up to six players must survive increasingly tough hordes of grotesque monsters. Already a hit on Steam, Killing Floor 2 has finally arrived on Xbox One, with exclusive content.

In 2005, the first Killing Floor came to life as an Unreal Tournament 2004 mod. The mod was so successful, developer Tripwire Interactive acquired the rights and released Killing Floor as a full game in 2009. The weird sci-fi aesthetic and clever co-op elements of the original made for a truly unique game (and a fine alternative to the Left 4 Dead series). Sadly, it never came to consoles. Killing Floor 2 started its life as a Steam Early Access game before fully launching on Steam and PlayStation 4 in 2016. After a painful period of timed exclusivity, it's now available on Xbox One. New content includes equippable Wasteland armor for every character, a freezethrower gun that freezes enemies before shattering them, and built-in Mixer support (enabled under Gameplay Options). Xbox One X graphical enhancements are due out in November as well. Best VPN providers 2020: Learn about ExpressVPN, NordVPN & more

In Killing Floor 2, the Zed (zombie and monster) outbreak has spread across the world, toppling governments and sending civilization into chaos. The biotech firm Horazine (which created the virus) must now fund a group of civilians and mercenaries as they attempt to establish outposts amid the chaos. This story is told not through the game itself, but the game's wiki. Killing Floor 2's presentation is a bit bare bones in that regard, with all of Tripwire Interactive's energy having been put the into level and gameplay design rather than a narrative. And for a heavily multiplayer-focused game, that's not such a bad thing. Fighting off the horde

Killing Floor 2 offers three game modes: Survival, Weekly, and VS Survival. Survival is the main game mode, with one to six players cooperating against enemies. Weekly is a high-level variant that changes every week, changing the enemies that spawn or other factors. VS Survival is a 12-player, team-based mode in which one side plays as humans and the other controls the monsters. Although the original Killing Floor competed head-to-head with Left 4 Dead sales-wise, Survival mode is structured much more like Gears of War's Horde mode. The host player selects a game length of four, seven, or 10 waves, and then players must work together to survive. After completing the last numbered wave, the game ends with a boss wave.

Part of what makes Killing Floor 2 so unique is the motley assortment of enemies created by Horazine. Nearly every single one of the 12 enemy types also appeared in the first game – the developers could have created a few more to better differentiate this one. But they look dramatically better and provide plenty of challenge for players. You'll battle zombie-like monsters called clots and cysts, Left 4 Dead-like spitting bloats, screaming sirens, spider-like crawlers, and more. The tank-like fleshpound is particularly grotesque and takes a ton of damage to kill. Even when they're reminiscent of foes from other games, the Zeds look distinct and gross – more like Resident Evil foes than Left 4 Dead zombies.

Between waves, the female shopkeeper (who doubles as a narrator) directs players to a specific location in the level. There, they'll spend money earned from kills to buy armor, ammo, and weapons for the next round. This rotating shop location is clever game design that ensures players will experience different areas in the vast levels instead of just holing up in one location. Players can even give money to each other, helping less fortunate teammates (or those who join mid-game) buy better weapons. Sharing money like that is frequently important, because you lose all purchased equipment and some of your money when you get killed. Death can come fast if the Zeds catch you alone or box you in during the heat of battle. And owing to Killing Floor 2's old-school nature, players can't revive each other – not even the medic can. You'll come back to life if your team wins the round, thankfully.

The make-or-break moment in each game is undoubtedly the final boss wave. Killing Floor 2 only has two different bosses: the returning Patriarch, the mutated former CEO of Horazine; and Dr. Hans Volter, an exo-suit-wearing mad scientist. The lack of boss variety is certainly a detriment. No matter which of the two bosses you encounter at the end of the game, there's always a feeling of repetition. Still, both bosses are extremely tough to beat. Patriarch can turn invisible to escape the team, fully healing when he reappears. Hans Volter has a rechargeable shield that absorbs all damage until it's destroyed. Both are capable of killing foes in just a few hits, and their life scales with the number of players in the game. That challenge comes with a great sense of reward when you beat them, not to mention a ton of XP. See our boss guide and beginner's guide for plenty of tips on beating both bosses. Characters and classes

XP contributes to your class of choice. Killing Floor 2 offers a whopping 10 distinct character classes. A few classes like the gunslinger seem like filler, but many are designed to play a valuable role on the team. The medic can use healing grenades to heal at long range; support provides free ammo refills to teammates; demolitionist gives out grenades; and more. You earn XP for a class by getting kills with that class's weapon or performing class-focused actions like sealing doors. Anyone can wield any weapon, making it possible to mix and match XP between classes. Every five levels, your class of choice gains a new skill as well. You can choose between two different skills per level, allowing some customization. Higher level skills are extremely useful, greatly increasing the team's chance of survival.

In addition to choosing your class, you also get to pick between 14 different characters. Killing Floor 2 only offers two female characters, both white, but the male selection spans multiple races. Characters can be further customized with clothing and accessories won as random drops or bought via microtransaction. Microtransactions

While Killing Floor 2 is an excellent game, its DLC and microtransaction implementation leaves much to be desired. Gamers can buy two types of items, neither of which are essential in the least: loot box keys or cosmetic clothing bundles. Most of the boxes I've encountered contain one random weapon skin, and a single key costs $2.49. That's not a good value. As for clothing bundles, the game offers six such bundles at launch for $5 each. But each bundle is tied to a specific character. For $5, I want the motorcycle outfit to be equippable by anybody – not just one character! And that still leaves eight characters with no premium clothing options. If Tripwire is going to bother to sell premium clothing, the outfits either need to work for everybody, or everybody should have some kind of outfit for sale. Overall impressions of Killing Floor 2