Killing Floor has gotten a free update with a new Portal-themed prototype level. The release is a complete, fully-functional level that isn't quite due for official release. The official press release claims that the developers are investigating the source of the "leak", but encourage everyone who owns Killing Floor to explore the new level and report back on what they find.
Killing Floor is currently available on Steam at a 50% discount, and is included in the full Potato Sack release containing 13 great indie titles.
