Quake, So what is this?

It's pretty old skool, with superb graphic, you battle a bunch of cyborgs and sometimes fight alongside allies who can dish out quite some damage themselves too. You can get your armor repaired or be healed by engineers and medics respectively, (or get healthpacks). There are some cool looking bosses, but they're not too special in fighting. It has some vehicle scenes which are pretty easy but are nice. There's a really cool stroggification scene in which you're turned into a cyborg, which gives you some extra health, allows you to use enemy health stations and you walk faster.

I really enjoyed the game, one of the funnest games IMO, but doesn't have much replay value.

There are a lot of cools scenes, and though the story isn't the thickest it is incredibly well acted out.

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Unless you're not talking about nr IV (4) 

i'm not sure which quake you're talking about. Most likely quake 4, so in that game, it's a real simple run and gun game. It doesn't require much thinking and the only annoying thing is how incredibly linear it is and that it's something that you've probably done already. It's still a fun game to play though, and the multiplayer is good.

If you're talking about the others, i know there's a pack out there that gets you the first 3 quakes for 10 dollars, then quake 1 and 2 are really fun games that are completely run and gun, but the level design is very good and it's fast paced. Quake 3 is a really fast multiplayer only game that has a loyal user base and is very competitive. The only thing that someone might find annoying about these games is that they're fairly dated, but that shouldn't stop you from getting them.