Mexxa Rien was introduced in issue 69 of New Warriors as a Nova Corps member assigned to Garthan Saal as a liaison after Richard Rider's rank was revoked due to insubordination over a direct order. Mexxa's main personalities her cheerful nature and sharing private information, the latter also including giving petty jokes in messages. Both Mexxa and Saal had shown to be friends as both of them mock their quirks in a friendly manner, which Saal call Mexxa as "What's The Gossip" for her tendency to share private information between her fellow Nova Corps members while Mexxa teases his obedience nature as "Orders are orders". Her main duties for Garthan Saal involved delivering messages from Worldmind and commanding officers of Nova Corps, including one of the routines where both of their conversation and message deliveries cut short when New Warriors were battling Sphinx. In her last appearance, she provided the last order of recall to Garthan Saal who became suspicious as she showed a somber mood rather than her cheerful demeanor. After Garthan Saal's presumed death, whether she was reassigned to a different Corps member or continue with Richard Rider remained unclear.