Litwick

Litwick has a fun time bothering Phantump about him being too nervous to share his exact origins. Litwick had also killed Tree-Rex by tricking him into going into a deep dark cave with her, after absorbing all Tree-Rex's life energy, she ended hiding his body. The last we see of Litwick in episode 16 was her just bullying Phantump until she gets beaten up by Baby Squirtle, Sandile, and Manta Ray.

In Episode 21, Litwick had lost her flame, afterwards, being audibly sick throughout the rest of the episode 21.

In Episode 22, she isn't there, she remains sick until being able to compete in Episode 23.