Seriously. I mean that when I say "fist". One of the most entertaining things about this game is weakening enemies with firepower before running up to them to finish them in a gory "glory-kill", where you punch through their chests, rip out their spines, tear off limbs, and other cinematic ways to defile your enemies. That's pretty much the main appeal of the game; killing monsters in bloody ways, either through your fists or any of the multitude of weapons you pick up throughout the game. Which does include a chainsaw.
The controls are pretty standard for FPS games, and are pretty clean and bug-free. I haven't had any problems with the graphics as far as bugs go. Granted, this is really a pretty simple game, so there's not much to screw up.
The graphics are great. About as one would expect with the current technology level of systems. Levels are detailed, backgrounds are cinematic, and enemies are complete. Even the glory kills are thought out and detail oriented, most of them having just the right about of splatter and viscera depending on what angle you hit the enemies from. For all the blood and violence, it really is a visually appealing game.
As far as gameplay though, be prepared. Despite not being my preference, I'm not a FPS noob. I've played my fair share, so when I started up DOOM, I figured I didn't have to go the baby route of the easiest difficulty. I was wrong. This isn't just a FPS. It's very fast paced. You have to keep track of your health, your ammo, your enemies, and your environment, all while constantly moving to avoid being shot, burned, slashed at, and managing to return fire so you don't get overwhelmed by numbers.
The game also includes a multi-player mode, but it's honestly a bit lackluster compared to the rest of the game, likely added in to give the game a little more longevity and for the players who live for player-on-player action (PVP). There is talk of some downloadable content coming for it, but I'm not sure if that'll be more levels or PVP stuff.
Overall, this game appeals to fans of the originals, Horror fans, and will serve as a good, quick distraction for PVP players who burn out on the latest COD or Battlefield. If it sounds like fun to you, don't hesitate to grab it if you can get it used or on sale. Definitely a fun shock to the system, especially for a game you're really only likely to play through once.