Shadow Pokémon (Japanese: ダークポケモン Dark Pokémon) are artificially altered Pokémon produced by Cipher in Orre. Collecting them via snagging and restoring them to normal is the main goal in Pokémon Colosseum and Pokémon XD: Gale of Darkness.

Shadow Pokémon are created by artificially shutting off a Pokémon's emotions, turning it into a souless fighting machine. Ein, the brains behind the Shadow Pokémon process, refers to this as "shutting the door to their hearts". Shadow Pokémon radiate a black aura that cannot normally be seen. However, Rui's psychic abilities allow her to recognize the Shadow Pokémon aura on sight, and the Aura Searcher can detect this aura as well. Shadow Pokémon do not gain Experience in a Pokémon battle, and they start with only Shadow moves. Ein's research was later picked up and expanded upon by Lovrina.

Shadow Pokémon sometimes behave oddly and irrationally, entering feral states called Hyper Mode or Reverse Mode. In both states, the Pokémon is difficult to control and may do itself more harm than good. Calling to a Shadow Pokémon, using a cologne on it, or leaving it at the Pokémon Daycare will snap it out of either of these states, and helps restore it to regular Pokémon.

There are several ways to purify a Shadow Pokémon; their effectiveness varies according to the individual nature of a Pokémon. Purifying a Shadow Pokémon helps it regain its original moves and personality. When a Pokémon is finally purified, it will gain all the experience it could not get as a Shadow Pokémon, regular moves instead of Shadow moves, and a ribbon.

Pokémon Colosseum

Shadow Pokémon available

Unused Shadow Pokémon

According to unused text in the game, the following Shadow Pokémon were originally planned for the game, but never used:

• Kecleon
• Minun
• Spoink
• Baltoy
• Castform
• Psyduck
• Teddiursa
• Wobbuffet
• Wailmer
• Porygon2
• Xatu
• Whiscash
• Magcargo

Pokémon XD: Gale of Darkness

The role of Shadow Pokémon in Pokémon XD is overall the same as in Pokémon Colosseum, although more than one Shadow Pokémon may appear in a battle, Shadow Pokémon know many more Shadow moves than just Shadow Rush, and once purified a Shadow Pokémon gains a special move that it would not learn otherwise. The main storyline centres around a Shadow Lugia. Also, unlike Colosseum, XD features Kanto-native Shadow Pokémon.

Shadow Pokémon available