Meta Groudon is the antagonist of Jirachi: Wish Maker.
Butler was assigned by Team Magma to bring a Groudon back to life using a Fossil of the prehistoric Pokémon. Unfortunately his experiment failed as his machine lacked the proper amount of power. This got Butler exiled from Team Magma, and was the sole event that caused his hatred to boil and to seek revenge on the organization. Butler then planned to use the power of the millennium comet to complete his experiment, and was in need of a Jirachi which could channel the comet's energy. Some time later, Butler found the Jirachi he had been searching for in the land of Forina.
After the Jirachi had awaken from its thousand year sleep, Butler successfully finished his experiment. Unfortunately, his creation was pure evil, rogue, and began absorbing the energy from the earth as well as living organisms such as plants, people, and Pokémon; including May, Brock, Diane, Jessie, James, Meowth, and many of the wild Pokémon; with gelatinous tentacles expelled from its spikes. After seeing the error of his ways, Butler decided to aid Ash in destroying his own creation by reversing the polarity of his machine. However the Groudon had to be near the machine for it to work, and Jirachi had to once again charge the energy gained from the comet. Butler distracted the Groudon on his Salamence while Ash and Max rode on the back of a wild Flygon to Butler's machine. They barely escape being eaten themselves when Salamence swoops in front of the Flygon. Salamence however is caught in the tentacle and Butler is sent falling to his doom, only to be rescued by Jirachi teleporting his Salamence under him just in time to catch his fall. Once Jirachi is fully charged, Butler, his Salamence, and the Flygon are caught by the Groudon who has enveloped the machine with its enormous body. Jirachi unleashes its Doom Desire and sends the Groudon high in the air where it is then obliterated.
After the Groudon was defeated, all of the people and Pokémon it had eaten were revitalized.
It was suggested by many Japanese people that this false Groudon strongly resembles Daidarabotchi the Nightwalker portrayed in the Princess Mononoke by Studio Ghibli, in terms of its abilities, behaviors, and the scene of melting during its corruption.