is a video game. It's basically what Fallout or Borderlands would be like if they were made by ID Software, and not, y'know, by companies who make GOOD games.
It is a pure FPS, no levelling or character progression choices beyond "Now I have a Machine Gun Ho Ho Ho". It is PRETTY AS FUCK, no, seriously, this game looks awesome. It's a decent FPS, without falling into the design traps of ID's previous games. It's got nods to nonlinearity and some side missions that are great fun, but it's linear. Really, really linear. Half-Life or Bioshock linear. It PRETENDS to have an open world, but the world really isn't open, and the levels specifically once you choose a mission are straight lines with the occasional secrets.
Perhaps the best description of it I can give is "a way prettier Half Life 2, with a less interesting story, a MUCH better combat engine, and the option of doing some of the missions out of order and some challenge missions that you can choose to skip."
It is WELL WORTH the $5 I paid for it, and that you can pay for it, right now. I can see EXACTLY why it's got a $20 non-sale price. Had I paid $60 for it new when it came out, I would be pissed.
But for $5, it's a good game, worth looking at.
And there's a co-op multiplayer that I haven't gotten a chance to try yet. That could be fun.
: While there are combat setpieces, there are relatively few Doom-style "Okay, I've stepped into an obvious combat zone, now all the perfectly normal walls will retract and enemies will jump out of places they could not have been hiding" setups
: So far.