Killing Floor.

In case any of you have never played, Killing Floor is a FPS co-op game built on the Unreal Engine. The point of the game is simple: Fight back the swarms of zombies that are attacking. There are various elements of the game that seem like they've been stolen from other zombie concepts, IE genetic engineering gone wrong, and different mutations of zombies like in the L4D/2 games. However, it puts enough of a twist on these characteristics to make them at least a bit original. The downside I see in this game is that there's no campaign, so after a while it gets a bit stale, but according to Steam I've played about 80+ hours of it and I'm still having a great time. The problem with the steam version is that it runs about $20, and definitely is not worth it. I recommend either waiting for a Steam sale (I think I got KF for about $9, which is a much more accurate price), or pirating. While the latter solution will prevent you from connecting to steam servers, there are cracked servers that should allow you to connect. Check here for a list of some of those servers. My favorite aspect of the game is the perks feature: Different areas of specialization as you would see in any military setting such as medics or demolition experts. A complete and comprehensive list of these perks and their many attributes can be found here on the Killing Floor Wiki. My favorite, if anyone was wondering, is support specialist. With their specialty in shotguns and welding, they make a very formidable and useful team mate. One trick I love using is sitting in a room and welding the door shut. When you do this, the zombies that are coming for you will all gather at the door and work together to break it down. Usually by the time the door breaks down, you can have a group of 10+ zombies. The shotgun works well for taking out multiple zombies at a time (depending on their health/mutation) so two shots could take out all or most of these 10+ zombies, especially if you use well-aimed headshots (their heads are much weaker than their bodies). Today I successfully hacked all of those perks up to level six. If anyone is interested in how to do this, just let me know. If you have Steam and want to add me, my profile can be found here. I own a few games but typically only play Half Life 2: Death Match and Killing Floor. If you choose to pirate Killing Floor and want to play with me on a cracked server, you can shoot me an IM on AIM (xmrlinuxx).