My reference

This knight is a result of mages' attempts at creating an invincible soldier for king Mordgar's army. Going through such a transfomation was considered to be a big honor for any court knight, and a great risk at the same time. Noble sir Tollen volunteered to become the first of this new kind of soldiers, for his loyalty to the king had no limits.
But mages, in their hubris and arrogance, tapped into elemental powers, which were far beyond their comprehension, and lost control - both over the experiment, and the newly created monster. Sir Tollen, now consumed by primal fire raging in his body and soul, started slaughtering, and didn't stop until even his beloved king was dead.
In their last attempt at stopping the monster, the few remaining mages managed to trap him in a vessel of magic metal and send him to the fartherst corner of the continent.
Legends say, the Knight of Flames still wanders aimlessly trough wilderness, still encased in his constantly melting armor, spreading smoke and fire everywhere he goes.
