Shaymin

A Shaymin is a Pokemon from Sinnoh who debut may have been as early as season one, but is only proven to exist in season four.

Physical
Shaymin is a small, white hedgehog-like Pokémon. In Land Forme, it has green grass-like fur on its back and a pink flower with two leaves on each side of its head, which resembles the Gracidea flower. Its legs are short and its underside is plump. In Sky Forme, it has a slender, canine appearance with resemblance of a small reindeer. The fur on its back becomes a mohawk, and it has a red flower petal on the right side of its neck, resembling a scarf or cape. It has flat, white ears resembling wings, a small ruff on the front of its neck, and a stumpy tail. In the show, Shaymins can talk but also make a floaty "myuuh" sound similar to the one in makes in the anime.

Powers
In Pokemon, Shaymin has powerful natural abilities, able to turn desolate landscapes into lush, flowery hills. Shaymin may possess this ability in Cartoon House, but it has not been shown. Shaymin has been known to have an extremely powerful happy aura that causes people to produce happy waves when around it. As a result, Shaymins are extremely expensive creatures.

Seasons 1-3
Shaymin may have appeared in the first three season, but there is no proof.

Season 4
In season four, there were two Shaymins who loved pillow pets living in the Pokemon Daycare. They were established as fairly lacking in intelligence. Shaymins didn't have any more extremely important appearances until season ten, and these two characters in particular haven't been seen since.

Season 10
In early season ten, the short story titled "Happy" was posted by one of the show's creators. It was about Ivan and a Shaymin being tortured. They would have the two meet occasionally, each time causing them to become extremely happy, so they could collect the happy juice, then bring them apart. Eventually, Ivan escaped with the Shaymin and returned home, naming the Shaymin Happy.

Appearances
Rief's Insanity?

Return of the Fangirl Invasion