From Bulbapedia, the community-driven Pokémon encyclopedia.
Purification, or "opening the heart's door", is the only known method of changing a Shadow Pokémon back into a normal Pokémon. It is used in Pokémon Colosseum and Pokémon XD: Gale of Darkness to restore any Shadow Pokémon that Wes or Michael have snagged. Purification can be seen as a main goal in those games.
Purifying a Pokémon
Before completely opening the door to a Shadow Pokémon's heart, its Heart Gauge must first drop to zero, turning completely white.
The following things will slowly open the door to a Pokémon's heart:
(note, using hoppip in the purification chamber is recommended, because hoppip is good against itself. Tropius can also be used but is not catchable in game)
- 0% Purified: The Pokémon has at least one Shadow move, its nature is unknown. This is the state at which a Shadow Pokémon is snagged.
- 20% Purified: When at this stage, the Shadow Pokémon will relearn a move.
- 40% Purified: The Shadow Pokémon's nature is revealed (though it was determined when the Pokémon was snagged).
- 60% Purified: Another move is relearned.
- 80% Purified: The Shadow Pokémon will enter Hyper Mode more frequently.
- Empty Shadow Bar: Shadow Pokémon's heart is 'ready to open', the Purification process can be finished, turning the Shadow Pokémon back into a normal Pokémon.
Once a Pokémon's Heart Gauge is completely white, it is time to "undo the final lock," the final step in opening the door to a Shadow Pokémon's heart. This is done through a Purification Ritual. In Pokémon Colosseum, Purification Rituals can only be performed at the Relic Stone in Agate Village, but in Pokémon XD: Gale of Darkness, they can be performed in a Set of the Purify Chamber at Pokémon HQ Lab as well.
A special item, the Time Flute, can be used to purify any Shadow Pokémon instantly. Playing this item will make Celebi appear, and it will open the door to a Shadow Pokémon's heart. A Time Flute can only be used once, and only a few appear in Pokémon Colosseum.
Time Flutes do not appear in Pokémon XD: Gale of Darkness.
Shadow Lugia, (codename: XD001), is a special case and can only be purified if it is put into one of the Purify Chamber's Sets with all nine slots set to maximum tempo.
Once a Pokémon is purified, any Shadow moves are replaced with other moves. In Pokémon XD they learn each of these moves: one move learned through level up, one move learn through a TM, one egg move and a special move. It gains any Experience that it has earned in battles prior to the purification meaning that it may gain one or more levels. The Pokémon receives a special Ribbon for "clearing all difficulties", and at this point the Pokémon Trainer may choose a nickname for it. The player may also trade the purified Pokémon with the GBA games Pokémon Ruby, Sapphire, Emerald, FireRed, and LeafGreen using a Gamecube/GBA cable, but only if the player has defeated the Elite Four (Template:Gameabbrev2) or located the Ruby and Sapphire and given them to Celio (Template:Gameabbrev). The player of the GBA games must also save in a Pokémon Center with the Pokémon they wish to trade to the Gamecube game.
The following Pokémon can only gain certain moves if they are a Shadow Pokémon purified in Pokémon XD: Gale of Darkness:
Moves like Helping Hand, Heal Bell, and Follow Me are present because almost every battle in Pokémon XD is a double battle. These moves can then be used in order to assist or protect the player's other Pokémon in these situations, making progress through the game easier.