A bug in the spell casting
While you cast a spell, there is a waiting period as the magic charges. To avoid this, when your spell begins to charge up, press the triangle button to bring up the pause screen, and pick the inventory selection. Return to the game, and the spell will be cast immediately.

RPG nerds FMV
A humorous Easter egg for all fans of pencil-and-paper role-playing games: during the credits, which you can choose to view at the main menu, press the X button. The drop-dead hilarious short movie shows characters from the game playing Dungeons & Dragons.