Which is odd, really, because Headhunter certainly culls a lot of ideas from elsewhere. There's a lean-up-against-the-wall-and-pop-out-to-shoot mechanic, stealth kills are in evidence (hold the left trigger down, sneak up behind an enemy and press A and he'll go down rather brutally), there's a combination scanner/map computer tool (for identifying breakable walls, locating objectives, and so on and so forth), there's a 'code breaker' (for busting down security doors, all of which seem to yield to simple join-the-dots or add-the-numbers-in-your-head style puzzles), there are little spider headcrab bastards to contend with, and there's an annoying streetwise female sidekick who spends more time on screen than our actual hero. Which is, in itself, something of a riff on Metal Gear Solid 2's character switcheroo, no?