Wizardry: Labyrinth of Lost Souls

Just get one character to level 30. Not much to say here - just don't class change at least one character (might most likely be your Bishop or Thief since you need those classes anyway) and get him to level 30. This should come naturally while processing through the game. Be aware of the enemies on the last two floors of Shiin's Dungeon since they can drop your level by up to 4 (at least that's the highest my level got dropped).

The trophy will unlock after one character reaches level 30.