There's nothing more petty than losing friends over video games -- but that doesn't mean we haven't all done it.
When you're really into gameplay, it's easy to let your emotions take hold of you. You may forget the times you've shared together IRL and instead focus on that extremely unfortunate blue shell hit in Mario Kart or how bad your friend is at drumming on Rock Band. And when that happens, you're tempted to scream and shout and shut them out of both your Facebook and your real life. In a green shell: you hate the player and the game.
These games are probably the biggest catalysts of the sometimes-not-so-friendly fights you have at LAN parties -- you've been warned.