Data exists for Battle CDs 51-60, though they can only be obtained by hacking. CDs 51-55 are incomplete, kicking you out of the challenge upon startup since you don't have a team (the game effectively treats this as a loss). CDs 56-60, meanwhile, are identical to some of the Battle Sim tutorials. Battle CD 00 is the Salamence vs. Metagross battle at the beginning of the game.
The game contains many unused maps, most of them test maps and leftovers from Colosseum, including The Under and Pyrite Cave (though without music, NPCs, PCs or Healing Machines). Also, it was apparently once possible to enter Greevil's cruiser while it's docked on Citadark Isle.
There's an unused item for "The key to the safe in the Parts Shop," and map descriptions for both The Under and Dark Colosseum, "A Colosseum built on Citadark Isle."
Through Action Replay codes, the player can start the game with a Lv. 26 Jolteon and a Lv. 30 Vaporeon instead of a Lv. 5 Eevee. Like the starter Eevee, they are listed as "Obtained from Michael's dad."
Some data left on the disk reveals that The Under was planned to appear in the game, but that the residents DID move out anyways, leaving the town abandoned.
Map Description: "An abandoned underground town."
There is also a map description for a "Dark Colosseum" on Citadark Isle.
Instead of an Eevee, the player was going to receive a Vaporeon and Jolteon as their Starter Mon. Their levels were 30 & 26 respectively, suggesting trainers were going to start off at higher levels and all battles would be double battles like in Colosseum.
This is the only Pokémon spin-off title to have its own box unique mascot.