Star Ocean: Till The End Of Time

To unlock Universe difficulty you first need to obtain 25% of the Battle Trophies; once that's complete you can play on Universe Difficulty. Universe Difficulty gives enemies a 1.5X buff to all of their stats, aside from that though not much else changes. If you're looking for tips while in this mode, refer to Toughest Challenge. Once you've beaten the final boss, the trophy will unlock.