Killing Floor has been around for a long time now, and has been incrementally successful as word spread of how enjoyable it is. I don't quite remember why I purchased it, perhaps I had tried it on a free weekend and was convinced. What I do remember is purchasing it for multiple friends almost immediately because it was a quality title. I have been playing it for half a decade or more, and it is just as fun now as it was in the beginning. The only thing that changed was the sense of progression, as I maxed out all of the classes.

Killing Floor 2 is the same game, nearly indistinguishable aside from cosmetics and perk dynamics. It is clearly not finished and I think there are some critical things missing, including entire classes, but the gameplay itself is addictive and had me hooked instantly. It is currently Early Access, so not being finished is part of the game description. This is the pinnacle of horde type games, the difficulty is fluid and will always keep you challenged. I never made it to Hell on Earth in Killing Floor 1, I have barely touched hard in Killing Floor 2.

As for performance, it runs smooth on an average system on high settings. It's gruesome, which is all I really wanted from a sequel. The same gameplay and feel with more blood and guts galore. The soundtrack is heavy, which I enjoy but its repitition quickly grows old and I end up using spotify in the background. Even as an Early Access game, where you basically pay to help beta test it, I highly recommend the investment.

Edit 8/26/2015: I came back to add a note about the development of the game. It has been excruciatingly slow with hardly any updates at all. If this is your first time playing Killing Floor, I would recommend that you play the original game for awhile. This one will feel like it is lacking heavily, and it is, but again, it is early access. I haven't touched it in awhile, as the game itself seems to be pretty solid and my participation hardly seems necessary at the moment. I will return when they update the content.

Edit 3/19/2016: The game is much more "complete" now, with almost all of the familiar classes from the original and a good amount of maps to keep things interesting. At this time I would say the game is definitely worth investing in. It is everything Killing Floor was with more. Like I said, the improved gore system is the primary appeal. Same game, more blood and guts.

Edit 11/16/2016: Alright, the game is considered complete. It will be released for the Playstation 4 in 2 days. The last update introduced the Survivalist class. It's not bad, I actually enjoy it, however it makes all of the other classes not matter. The idea of classes was to inspire teamwork, to have people dedicated to specific jobs and make the Zed killing easier. To make it so that people can just mesh it all together in one class and be just as effective destroys that premise. It's still good though, fun and mindless.

Edit 11/23/2016: The game has been officially released. It's great but could really use some content updates and by that I mean maps. I suppose community maps are the solution to that.