Sym-Bionic Titan - Season 1 - Eps 13: The Demon Within
Lance, Ilana, and Octus go deep in to the swamp to find a Mutraddi that has crash-landed in the water. They investigate the wreckage and are attack by an amphibian-like Mutraddi that, after a seemingly easy kill, is able to bite Ilana and escape. Very slowly she transforms into the creature and attacks an alligator that was also mutated. Lance and Octus discovered that if they kill the original Mutraddi she might turn back to normal. After a short battle they killed the original Mutraddi turning Ilana back to herself.
About Sym-Bionic Titan

Title: Sym-Bionic Titan
First Air Date: 2010-09-17
Last Air Date: 2011-04-09
Status: Ended
Rating: 8.454/10 (from 163 votes)
Language: EN
Seasons: 1
Total Episodes: 20
Network: Cartoon Network
Genres: Action & Adventure, Animation
Production Companies: Cartoon Network Studios
Synopsis
Sym-Bionic Titan is an American animated action science fiction television series created by Genndy Tartakovsky, Paul Rudish, and Bryan Andrews for Cartoon Network. The series focuses on a trio made up of the alien princess Ilana, the rebellious soldier Lance, and the robot Octus; the three are able to combine to create the titular Sym-Bionic Titan. A preview of the series was first shown at the 2009 San Diego Comic-Con International, and further details were revealed at Cartoon Network's 2010 Upfront. The series premiered on September 17, 2010, and ended on April 9, 2011. The series is rated TV-PG-V. Cartoon Network initially ordered 20 episodes; Tartakovsky had hoped to expand on that, but the series was not renewed for another season, as the show "did not have any toys connected to it." Although Sym-Bionic Titan has never been released on DVD, All 20 episodes are available on iTunes. On October 7, 2012, reruns of Sym-Bionic Titan began airing on Adult Swim's Toonami block.
Cast

Brian Posehn
Octus (voice)

Tara Strong
Ilana (voice)