1. Inspector Gadget
This guy loves all the bits and pieces associated with gaming. He actually bought the Nintendo Power Glove and the Virtual Boy. He has Rumble Paks on his Rumble Paks. Maybe he just really likes Nintendo... No wait, there's a stack of every color of PlayStation memory card ever made. He always shows up with his own controller in pristine condition, and you laughed at him when he brought over the Master Chief helmet that came with the Legendary edition of Halo 3, because it's tiny and you can't actually wear it. Then he used it to build a scale model that actually fit, and you were kind of jealous.
2. Freak of Nature
Ok, I thought pot made your reaction time slower. I thought being on the phone while doing stuff made you less skillful. I thought having played the game before would give me some kind of advantage. Yet here you are, high as a kite, talking on the phone with your girlfriend, never having played this game before, and beating the crap out of me. I don't know whether to salute you or cut you up into little pieces and hide them in the CD tray.
Doing stuff out of order just freaks this guy out. Don't ever invite him to play multiplayer on a level he hasn't played through himself on single player. He won't put down a game until he has every scenario beaten, every achievement achieved. "I'd love to play MF2 with you, man," he says, "but I'm still working on GTA IV." He still brags about how, at the age of 12, he got every star in Super Mario 64 in perfect order. You wonder seriously whether he puts this on his resume.
4. Old School Elitist
He's indifferent about games today, but oh man, were you alive when the first Super Mario came out? That game was tight. The mechanics, the controls, both groundbreaking and breathtaking. Halo can't hold a candle to GoldenEye; A Link to the Past leaves Uncharted in the dust. His reaction to any Call of Duty titles is lukewarm at best, though in a private conversation he'll admit he finds the realism of the guns frightening.