Their goal is to close off the hearts of Pokémon, which in turn makes them fighting machines. These Pokémon are known as Shadow Pokémon, and are used against both humans and in Pokémon battles. However, nurturing and loving the Pokémon eventually restores it.
Cipher has two leaders, but one of them is their "supreme leader".
 Pokemon Colosseum
Evice - The Cipher Head in Pokemon Colosseum. He works as both the Mayor of Phenac City (under the name of Es Cade) and the leader of Cipher. It is revealed that he is the leader at the very end of the game, when you are atop Realgam Tower. He is Cipher's strongest trainer so far.
Nascour - Nascour is the supposed head of Cipher, up until the very end of the game. He is first seen leaving the mayor's office in Phenac City, presumably having a chat with Evice.
Venus - Venus is the third Cipher Admin, appearing at The Under, an area in Pyrite Town. She is also a famous person, appearing regularly on TV. Her Shadow Pokémon is a Suicune. She is the only female Admin in Pokémon Colosseum.
 Pokemon XD: Gale of Darkness
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