Nuclear Knight 

Nuclear Knight was originally an early clone of Atomic Esquire created by Doctor Science, predating the creation of Atomic eXtreme. It was quickly noticed that although he had all of Esquires' DNA and his original pre-AtomicEsquire good looks, he had none of the powers and abilities. Doctor Science proceeded to brainwash him, encase him in a highly advanced nuclear powered battlesuit, and send back in time to destroy Hillary Plumington before he gained his powers. He found Plumington in the past and attempted to kill him and his companion; believing himself to be successful, he began making his way back to the pick-up point. Before he could be retrieved (if the Doctor truly intended to do so, that is), a newly-empowered Atomic Esquire found and defeated him, and his battle suit was rendered useless. The Atomic Esquire went off in search of Doctor Science, and the cloned Esquire was left, unconscious and undiscovered, inside.

After waking and prying himself out of the destroyed machine, the clone, brainwashing having worn off, realized what happened, and found himself to be now similarly endowed with atomic powers from the blast the armor being destroyed. Stumbling off, he eventually came across the charred remains of Plumington's companion, the knight, removed the nuclear-powered knight armor, and equipped it himself.

He decided to take the name of Nuclear Knight, and made his way off to find the Atomic Esquire, and help him take down his evil creator.

Powers and abilities:

The bulk of his powers, similar to Atomic Esquire's, come from his equipment; though he does show superhuman endurance and speed.

His primary tools are the Sword of Slashing (which leaves glowing nuclear paths where it is swiped that stay for a while), Rations of Eternity, and Shield of Energy Absorbing.