From I fic I'm thinking/plotting on writing.

Summary: Bodel(everyone usually blames Ulmar, so Ima stick this on Bodel XD) makes a battlegear that malfunctions during a battle with the Underworlders, explodes and turns Tom and Kaz into creatures(Overworlder and Underworlder respectively) and merges their code with their real selves.

Tom seems to take being creature a lot better than Kaz, but it's just a mask. Truth is he's terrified of the new feelings and instincts that his new form brings, especially the new feelings towards Maxxor that had originally been directed at Sarah...or maybe they are not as new as Tom thinks.

Intress was the one closest to Tom during the explosion and her form was 'written' into Tom's code. After Tom and Kaz escape from the CodeMasters, Intress looks after Tom like he was her own Kitten.

This not only puts a strain on her relationship with Maxxor but with Tangath Toborn as well, for both Overworlders want Tom for their mate and you all know how Feline Mothers can be very protective of their kittens.

Despite the their new forms Tom and Kaz are still best friends and when not in Kiru/Underworld city, they're helping Sarah and Peyton with Scan quests and exploring Perim in ways they weren't able to before.

Tom's Special Ability: Teleportation. But Tom hasn't learned to properly control it yet, so there's no telling where he's going when he teleports.