After No Face steals from the ISD a code card for the entire world's sattelite control systems, they send Action Force and Rebel to chase him down to the South Pole. Rebel has a personal interest in the mission since she's the daughter of Sir Arthur Strong, who was also captured by No Face under orders of Dr X.
After Action Man and Rebel get inside Dr X's South Pole base, they are captured by Coil Crushers and watch helplessly as Sir Arthur is toxified with the DNA of all animals and X himself, which turns him into Tyrannotox.
When Dr. X blows up the whole facility, Rebel is able to steal information from his computer before everything explodes. Then Action Man and Rebel make their escape Thunderwing Jet carelessly left by Dr X when he abandoned the site.
Action Force, including Rebel, arrives into Dr. X's new base, an island on the coast of Chile shaped like a giant X, and de-toxify Sir Arthur, who is reunited with his daughter.
Rebel's CGI character model seems to be based on the G.I. Joe character Scarlett (Valor vs Venom version) with black clothes.