Unlockable: Bonus Dungeons
After beating the game it will be saved as “clear”. Loading this game will take you to the Spiral Tower save point before the boss battle. Go down the stairs and talk to the bunny character to travel to the Fire Wall, the Ruins of Mosel or Surferio. The bonus dungeons include the Aquatic Gardens of Surferio, Maze of Tribulations, and the Urssa Cave Temple.
Unlockable: The Ancient Books
After defeating the Mudman, head out West out of Peterny and then go to North to Surferio. Find Roger S. Huxley there and talk to him. He'll give you the Ancient Books (if you agreed to take him along in Duggus Forest).
Unlock 4th Dimension Difficulty
Collect 70% of the Battle Collection.
Unlock Cave Of Trials Dungeon
Beat the game, and a special bonus 10 stage boss dungeon will be unlocked.
Unlock Full Auto Mode
Complete 95% or more of the Battle Collection.
Unlock Music Test
Complete 60% or more of the Battle Collection.
Unlock Universe Difficulty
Complete 30% or more of the Battle Collection.