Highly evolved engine based on id Software technology, available under dual license (GPL, proprietary licensing for commercial use available).
Painkeep 2.0 - bug fix one. Single player made play-able with painkeep items / weapons. Minor bug fixes detailed in readme.txt. You need the main install (painkeep v2.0 beta) done first!
Played some coop with bots. Noticed friendly fire happening. With any weapon.
Since I never messed with coop, I'm not sure if this is normal or not.
Going to try a team setting, and if there is still damage from friendlies I'll put in a cvar to cancel FF.