User blog comment:Malchior712/The Missing Gloomix?/@comment-4238246-20110813172310/@comment-4167044-20110814022456

Yes. In the eisode titled "Shadow Phoenix," Darkar betrays the Trix in favor of Dark Bloom, so the Trix combine forces, forming into a single entity named the MegaTrix and attack him in retaliation. She's only seen in one episode.