Trex Magmawalker is a red baby T-rex and the son of Edward Magmawalker.
He've been knowed to be the youngest soldier of Imalion, due to getting himself accidentally signed in.
During the Imalion Wars, he's in the Magma Squad along with Captain Rocky, Commander Scout and Quinncy Parry. Trex soon leaved Imalion after the war ended, with the death of Rocky and Scout, leaving him with trauma.
Trex later become the leader of his own group, called Rider Boys, along with Willy Tornavelt, Andrew Tsunalton, Jim Thunderloch, and Minoranus Earthdawn.
He's also find out about the Elemental Beasts that have been knowned in the legend as the Tyroturn protectors in which they're sealed as Elemental gems. Six of the elemental gems were sealed inside of Trex and his friends.
As elemental form, Trex transform into Special Ops Trex (fire), Ultimate Trex (thunder) and Metal Trex (metal) and evolved into Mega Trex.