Newsbrief: Tripwire Interactive has announced that its now decade-old game series Killing Floor has brought in over $100 million in revenue since its start.

The original Killing Floor began as an Unreal Tournament 2004 mod that eventually took on a life of its own. The series now includes three tiles: 2009’s Killing Floor, 2016’s Killing Floor 2, and the 2017 VR game Killing Floor: Incursion. Between those three titles, Tripwire says the franchise has sold nearly 10 million units and attracted the attention of 15 million unique players.