How to unlock Jirachi, get all the discs, capture all the Shadow Pokémon, catch Ho-oh, purify Shadow Pokémon and catch missed Shadow Pokémon are some of the tips and hints that can be found in the Pokemon Colosseum Guide. There are also some glitches in the game that can be taken advantage of to get infinite PokeBalls or get rid of a partner.
One of the tips mentions that, in order to get Jirachi, the user needs to connect the Game Boy Advance, with Pokémon Sapphire, to the GameCube with the Pokémon Colosseum Bonus Disc.
The guide includes all the places where the discs R, U, D and L can be found. There is also a list of all the Shadow Pokémon in the game and a process to catch a missed Shadow Pokémon. Specifically, if during battle with another trainer, the user accidentally kills the Shadow Pokémon, he simply has to leave the area and return. The trainer will want to fight again, giving the player a second chance to catch the Pokémon.
To catch Ho-oh, two conditions need to be met. First, the user has to catch and fully purify all 48 Shadow Pokémon in story mode. Then, he needs to beat all 100 trainers on Mt. Battle. After beating the 100th trainer on Mt. Battle, Ho-oh will show up and will automatically be transported to the player's PC.