Pokémon Colosseum: The Animated Adventure (Japanese: ???, ???) is the first special episode in the ??? series. It was announced along with Pokémon XD: The Animated Adventure on May 9, 2014 at 9:00 PM EST; its release is meant to promote the sequel to Pokémon XD: Gale of Darkness, Pokémon Zero: Shadow Saga.
A young man named Wes steals a mysterious device from the strongly-guarded headquarters of Team Snagem. He proceeds to flee with an Espeon and Umbreon as Team Snagem's base explodes. Riding on a bizarre one-wheeled motorcycle, Wes comes to the Outskirt Stand, a dilapidated gas station. There, Wes learns of Phenac City from a man named Willie.
In Phenac City, Wes teams up with a mysterious girl named Rui who claims that there are Pokémon surrounded by dark auras that attack people. Wes and Rui visit Es Cade, the mayor, to report this. When Phenac City is taken over by a band of mysterious thugs calling themselves Cipher, Wes battles them, encountering their leader, Miror B. Miror B.'s personal underlings, Trudly and Folly, battle Wes, and the hero successfully snags their Shadow Makuhita, the first Shadow Pokémon he's ever encountered.
Determined to stop Cipher and prevent the Shadow Pokémon epidemic from spreading, Wes and Rui next travel to Pyrite Town, where Shadow Pokémon are distributed freely as prizes to winners of the town's Colosseum tournament. The local police are powerless to stop Cipher's actions, so they, along with a man named Duking, turn to Wes and Rui for aid. The two protagonists defeat Miror B. in Pyrite Cave, purging Cipher form Pyrite Town once and for all. Returning a Plusle Miror B. stole to Duking, Wes and Rui continue on their adventure.
Wes and Rui's next stop is Agate Village, where Rui introduces Wes to her grandfather, Eagun. Wes and Rui help protect the Relic Stone, the only place where Shadow Pokémon can be purified, from some Cipher members, and they continue on to their next destination, Mount Battle. Scaling Mount Battle, Wes battles a Cipher admin named Dakim, and he successfully snags the man's Shadow Entei. Learning that Entei is one of the three legendary beasts, Wes returns to Agate Village and proceeds to the Relic Stone to purify it immediately.
Wes and Rui learn that a Cipher Admin named Venus lurks in a place the Under, and it is there that Wes successfully snags a Shadow Suicune. Meeting some kids from a Cipher resistance group called Kids Grid, Wes and Rui next proceed to the Shadow Pokémon Laboratory, where Shadow Pokémon are produced. The final Cipher administrator, Ein, challenges Wes to a battle, and Wes snags the last of the legendary beasts, Raikou.
Wes's final challenge comes when he learns that all of Cipher's administrators have gathered at Realgam Tower; in Realgam Colosseum, he faces off against Cipher's second-in-command, Nascour, and the villainous group's true leader, Evice (who was disguised as the benevolent mayor of Phenac City, Es Cade). Evice battles Wes with the last of the Shadow Pokémon, a Shadow Tyranitar, and upon his eventual defeat, he attemps to flee with Nascour in a helicopter. The helicopter is shot down by a Ho-Oh just in the nick of time, however, and the leaders of Cipher are placed under arrest. Wes and Rui say their good-byes, their journey at an end.
Some time after Cipher's fall at Realgam Tower, Wes and Rui team up once again when they receive strange reports of a man dressed like Wes attacking others with yet another Shadow Pokémon. The person who dares to impersonate the hero of Orre awaits Wes's challenge at the Outskirt Stand; Wes readily accepts and finds his "evil twin" to be none other than Fein, a disguised Cipher peon. Will Wes have what it takes to defeat Fein and clear his name of the recent Shadow Pokémon attacks? The adventure continues...