Killing Floor: Looking back at how it came to be 15 years later

Ten years ago, from the hands of Tripwire Interactive, the world got to know the horrors of Killing Floor, a six-player cooperative survival shooter that puts the players against hordes of bioengineered mutants known as Zeds on a frenetic experience.

Its gunplay features gore, slow-motion effects that, aside for being a lifesaver most times, also serve as a closer way to enjoy the spectacle around the dismemberment of the bloody vermins that want to devour us. Oh, and there are also cheesy and hilarious one-liners with British accent and slangs.

But before becoming the standalone game we know today, Killing Floor started to gain its popularity as a mod for Unreal Tournament 2004 fifteen years ago. It first started as a mod project for Battlefield which, due to some differences between the development teams and complications found with both the mapping and code management tools, was left abandoned.

The eagerness of Alex Quick, who started as an artist for the original project, pushed him to take the lead of the development and resurrected it in the process, found its new home as an UT2k4 mod. It quickly started gaining notoriety on Unreal forums and coverage by video games media and received the editor’s choice for Best Multiplayer Mod award in 2006 on moddb.

Alex was then approached by Tripwire Interactive, the studio that offered him to port the mod to their own game Red Orchestra: Ostfront 41-45, which was also based on UT2k4. But nothing came out of this first contact. A few years passed by, and the Unreal Tournament 2004 community started to disappear. Quick approached Tripwire to resume negotiations, which involved porting Killing Floor to Red Orchestra and the subsequent distribution on Steam, as result of this second negotiation, Tripwire considered that Killing Floor had a much brighter future than just being a mod, so they offered to purchase the rights to the game.

A standalone version was announced on March 2009, and Tripwire Interactive took the role of developer alongside the original mod team. Three months later, Killing Floor was released on Steam.

The game was a success; it only took it a few days to get to the top-selling list on the platform. Reviews brought up comparisons with the everlasting Left 4 Dead, and while the similarities were clear, both being coop first-person shooters that put the players against hordes of zombie-like enemies, there was much more to it. The aforementioned gore elements, and the slow-motion effects, known as Zed time, helped Killing Floor were the first elements that helped to build its own identity.

Aside from different gameplay mechanics, the game possesses a perk class system with RPG elements. Players have to accomplish certain objectives to bring up every perk to its maximum level, such as performing hundreds of headshots and wielding dozens of doors. This ensured replayability, and the plethora of weapons for each class, which only increased over time with DLCs and community packs, expanded these possibilities even further, maintaining the game fresh and allowing players to experiment with classes and weapons that better suit their playstyle.

Killing Floor started as a diamond in the rough, wrapped in the hands of people carrying the ambition and eagerness to make an entertaining game close to the original idea. And its legacy in itself proves it. It became a critically acclaimed game thanks to a formula that is still relevant and unmatched to this day, which also spawned a sequel and spin-offs. It deserves recognition during its 15th anniversary, and this should carry onto the ones that will come.