Rusty
Rusty [ 1 ] [ 2 ] (also known as the Fire Knight Mech or the Fire Tech Mech [ 3 ] ) was a sentient Fire Battle Mech created by the Fire Master . At some point in the past, it failed to assist the Fire Master and vowed to never fail any Elemental Master of Fire again. Kai would find him and restore him, where he would go on to sacrifice himself to save Kai and Daidan. .