Prior to starting a match, the player selects one of several perks (or classes) that represent basic combat classes (e.g. A patch released in early 2016 included a dynamic difficulty option in which a computer-based 'Game Controller' can alter the strength of subsequent waves, either making them easier or harder based on the players' performance. The number of waves in a match can be configured, and four difficulty levels are available: Normal, Hard, Suicidal, and Hell on Earth (ordered in increasing difficulty). The Trader is only open for a limited time between waves and in certain locations around the map. Players gain monetary bonus for surviving a round, which they can use to buy and/or sell body armor, ammo, and weapons at a store, also known as the Trader. The mission will fail if all players die before completing a wave. Once a player's health reaches zero, they will die and will not respawn until the end of the wave. When damaged, players can restore their health using a medical syringe on themselves or having a teammate use theirs, among other regenerative items. Once they spawn, Zeds chase and attack players automatically. Achieving certain types of kills, such as a head shot, may cause the game to enter 'zed time,' when all game actions for all players are slowed down for a few seconds, providing more time for players to adjust their decisions amid battle. When players kill a Zed, they earn in-game money and experience points.

Random weapons, ammo, and armor can be found by exploring the level, though players have a limited amount of weight they can carry. Players equip themselves with melee weapons and firearms, a healing syringe, and a welder used to block passages. The boss character is determined randomly upon the start of the last wave, and each boss is defeated differently. Enemy count is determined by the number of players in the game. As waves pass, the enemy count will increase different enemy types are introduced as players complete each wave, culminating to a boss fight as the final wave. Gameplay consists of players fighting through waves of zombie-like specimens, known as 'Zeds'. In Killing Floor 2, taking place a month after the first game, the outbreak has spread beyond Europe, causing governments to collapse and communication systems to fail. The clones have now rapidly spread across Europe, paralyzing the response from the European Union. The game is based on events from Killing Floor, in which bio-tech firm Horzine attempted to create military clones and was hijacked by an insane researcher who unleashed the clones across the UK. Killing Floor 2 is a first-person shooter video game that can be played alone or cooperatively with up to six players.

The player running into a group of Bloats

Killing floor 2 nightmare map