In Training posted:

Reset the league until you get a prize you want, recruit a bunch of OP low level characters from certain parts of the game, play a game until you're leading by at least a goal and then stand in net until time runs out. I did all the blitzball stuff in one sitting. Same with the monster capturing, I printed out a bestiary i made myself in Microsoft word and sat down checking off monsters as I captured 5 of them. I started doing this one night and without even really realizing it I looked out the window and the sun was rising