Delvil

Dialga rules time, and Palkia rules space, they lived in an alternate dimension so they decided to fight within their own reality, which would make it bad for the real world too. Dialga and Palkia appear before Ash and his friends and drag the city into their own world. If they destroy this city, they'll also destroy the whole world. Source: ANN

This is an animated cartoon that was released inside the game Pokémon Channel. A half-hour long anime show, broken into five short segments, featuring the Pichu Brothers. Meowth throws a party that the Pichu brothers and their friends are not invited to. After a series of events, they find out they were invited, but their invitations were simply delivered late. They go to…