4. Conker (Conker's Bad Fur Day)
Most games start out with some sort of tutorial to help you understand the game world and the controls you'll use. Not Conker's Bad Fur Day though, which starts you out as an alcoholic squirrel trying to make his way home after a night of binge-drinking. Your vision is blurred, you're stumbling aimlessly, and you have to piss every few minutes. In his drunken confusion, Conker gets lost - which leads him on a journey that has him smashing metallic testicles, fighting opera-singing feces, and ultimately watching his girlfriend die in front of him and be sucked into the endless void of space. And, worst of all, still no Zach Galifianakis.
3. Christopher Blair (Wing Commander 3)
There's rarely as good a reason to get totally and completely blackout drunk in a videogame, but Christopher Blair's got a decent one: his lover has just been brutally disemboweled (also, he's Mark Hamill, and at this point in time he's gone from being in the biggest movie franchise in history to doing an FMV videogame featuring space lions). You have a choice: get super-drunk to help the grieving process, or try to deal with your grief in ways not involving alcohol (what those ways are will forever be a mystery). If you choose to get drunk, there's a problem - you're trying to fight a space war, and there's a battle going on. And drunks make for baaad pilots. None of the controls work right, making it pretty much impossible to not ruin your ship and be forced to eject. Then again, Christopher Blair would eventually turn into Freddie Prinze Jr. for the movie version, so maybe there are worse fates than death.