Steam is having a free trial of Killing Floor this weekend, and I spent some time with it. Let me be frank. At first, I completely hated this game. The first draft of this review had nothing positive to say and was downright mean. I played it for another hour or so after that, and I came to understand it a bit better. As a mindless zombie killing romp, it does a decent job.

There are some interesting game mechanics that add to the interest. I especially game to appreciate the encumbrance / inventory system. Each item has a certain weight, and you can only carry so much. The weights are pretty carefully selected to force some difficult choices. For example, if you pick the Hunting Shotgun, that's the only weapon (other than the knife and 9mm) that you get.

While I'm at it, I really like the Hunting Shotgun. It's one of the better shotguns I've encountered in a game. It reminded me of the old Doom 2 double-barrel shotgun, and that's a good thing.

The use of headshots to prevent creatures from using their special abilities was also clever. However, pretty much all the creatures die within a few seconds of receiving a headshot, so it doesn't turn out to be that useful.

I eventually came to enjoy the interior maps. The welding torch, which is used to secure doors ala Aliens, is really cool. I eventually settled on running through the halls, welding a door shut, then running around behind the creatures that are trying to break through the door. It was very satisfying to unload both barrels on a big group of creatures lined up at a door.

Most of the exterior maps, especially the Farm, failed due to the crummy AI. Those maps basically degrade to running around until all of the creatures are behind you, turning around and picking them off one by one with the rifle. Either the AI needs to be better or something needs to change in those maps.

My main complaints are:

• Reload times on most weapons is way, way too long. This is especially true with the 9mm.
• When you're reloading, you're completely defenseless. You can't abort the reload to switch weapons, and you can't do any sort of melee attack. You can just stand there and get hacked to pieces. L4D got this right with the "shove."
• While I'm complaining about weapons, the AK-47 and the LAW are rubbish. The spread on the AK-47 is so wild that the weapon is almost useless. The one time I got the LAW, I couldn't get it to shoot. The game even goes so far as to mock you by saying, "If you're far enough to get [the LAW], you don't need weapon tips." That would be true if pressing the shoot button made it shoot!
• Limited time in the shop between levels. I understand having limited time to get to the shop. That's one of the game mechanics. However, once the entire team has gotten to the shop, the timer should stop. The existing setup punishes people for being unfamiliar with the game. The first few times you're in the shop, it's difficult to know what to buy. The interplay of encumbrance and item weights makes this even more difficult.
• One of the Ten Commandments of an FPS is "thou shalt have a crosshair." I understand that one of the main game mechanics is getting head-shots, but lack of a crosshair is still weak. I do have to give them some credit for fixing my other peeve with all other FPS games... you can use the "sights" on any weapon. It used to drive me nuts in Enemy Territory (as an example), that you couldn't use the sights on the M1.
• When you die, you get pushed to the next map set and lose all your stuff. Nothing is more frustrating than getting to 2 monsters left on map 3 of 4 and dying. Well... now it's an hour until you get to try that map again.
• I like death metal, but the soundtrack was just painful.

Currently the rating on Steam is 71. That's about what I would give it as well. For a $15 game, that's not bad. The problem is that there are a lot of other great games out there, and there are a few really good free games. I'll probably play Killing Floor a bit more this weekend. It may be worth $15, but I'm not sure it's worth my time.