Most obsessive compulsive thing you've done in a game?

Most of us have that ONE thing we have to accomplish in a game before we feel complete, whether it be getting a certain achievement, to maxing out a character, to farming a certain item for hours, days, or even months. Mine was farming all 252 of Gau's rages in final fantasy 6. Having to go through the organized list of possible sets of monsters for a 1/8 chance of it being the 1 monster you need can be nerve wracking. So share yours!

Finishing the game. I won't borrow games because I don't want to have the awkward "I need that back" "but I"m not done" conversation. Also, I get really ticked off when people concede a Magic game early (especially in multiplayer)

Castaways: I have to finish games 100% before im satisfied. I mean, if im paying x$ for a game, I want everything out of it. This excludes anything multiplayer since I dont have online. Watz: sure, card games can count ^^

All of my pokemon team in pokemon Y game are bred to have perfect stats. The pain of going through that process...I never want to do it again...

I suppose for me it would be getting all achievements/trophies... but I don't really feel like i have to play it during all my free time, but if i don't have a game that I havne't unlocked all achievements on then I feel the need to have it. If any of this makes sense