First some backstory.

Cozmo and Zilithia will both exist in my RP and probably my RP only. They are normal Cosmog... at first.

A few hundred years ago, Hoopa, wanting to test his powers after reforming from an alternate universe, challenged Lugia and Ho-oh to a battle. He claimed to be teleporting them to a battle arena, but instead closed the rings, sealing the two in the Negative Zone.

The Negative Zone is filled with shadows, darkness, and hate. It's enough to corrupt a Pokémon.

The now-corrupted duo escaped through a ring while hoopa was teleporting, but they weren't exactly free, for there is no true way out of the Negative Zone.

Their black bodies constantly glitch and fade as they are trying to be called back to the Negative Zone. Their only safe place, where they won't be returned to their own hell? Possessing another Pokémon.

And that's exactly what happened to Zilithia and Cozmo.

Cozmo's Appearance:

Zilithia's Appearance