Revenge of the Zeds (also known as the VS Survival) is an update for Killing Floor 2. It introduced the PVP game mode "Vs. Survival" where players can take control of modified versions of Zeds to fight against survivor players. There are 11 playable Zeds available. Playable Zeds include the Alpha Clot, Slasher, Crawler, Stalker, Bloat, Gorefast, Siren, Husk, Gorefiend, Scrake, and Fleshpound. The Patriarch is also playable. Certain playable Zeds have special attacks and abilities that the standard AI Zeds would not normally possess.
In addition to the addition of the Vs. Survival gamemode, the Revenge of the Zeds update introduced two new weapons, the Winchester and the Crossbow, into the game, as well as the map Prison with its own set of achievements.
Official description (from www.killingfloor2.com):
"We’ve all talked about this one for years – the ability for you not just to kill the Zeds, but the chance to BE the Zed – so here it is! In the all-new Versus Survival game mode, up to six players can be their normal, Zed-slaughtering selves, while up to six more can play as the Zeds. Work your way through multiple survival waves, all the way up to the Boss. Can the Human team make it through all the waves – or can the Zed team stop them before they get to the end? 6v6 PvP gameplay with every weapon, Zed and death!"