Rage

There stood the Dark Man. And there stood his enemy, calmly looking at him from just a few feet away. The only thing between them was a simple magic barrier - but one that the Dark Man could not cross, not even to crush the cur who dared oppose him. This was exactly what his nemesis, his glorious enemy, was counting on. To say the Dark Man was seething would have been quite an understatement indeed.
"Its not over," he said in a low voice. His words carried something to the effect of a promise in them.
"Yes," said his light-haired enemy after a few moments deliberation.  "It is." He spoke with ragged breath, squeezing his injured right arm, and after getting one last look at the foul creature on the other side of the barrier, he turned to walk away. He knew the simple click of his heels against the rock floor would enrage the mad egotist he was leaving even more than any conversation, more so if he never even had a chance to explain the brilliance of his thwarted scheme.
A sizzling, scorching sound, like the sound of desiccation, of all water being utterly dried up and extinguished, granted him pause in his footsteps and bid him to look past his shoulder at where he came from. The Dark Man's hands were pressed up against the barrier, black and purple flames issuing forth, but to no avail. He raised his hands and the sound stopped. The pain this caused him was evident - his eyes grimaced clearly, his hands balled into fists, his nostrils flared in quieted, barely contained agony. Their eyes connected. A second went by. Or perhaps a day did. And with a sudden yell the Dark One raised his scalded fists above his head and crashed them down upon the barrier, willing it with all his might to shatter, to rip, to tear, to crack, to chip, at least - oh gods, just let it chip, at least! just let a tiny, miniscule piece of it fail before him now!
But no such luck was to be had, and the gods could not hear a man who prayed only to his own power.
Slowly, the man with the silver-blonde hair began to walk away again. As he walked, rows of additional barriers would spring forth from the hard rock floor every few yards, semi-transparent and light-blue in color, shining for a few moments before vanishing from sight. As the Dark man was well aware of, these smaller barriers were not to prevent him from escaping; they were to prevent someone else from coming in. Once he reached the end of the circular chamber, the man looked about him once more, praying he would never have to lay eyes on this wretched place again.
They were deep, so very deep, into the belly of the Earth. So deep that the lifeblood of the planet - molten rock and fire - was visible here, and created ample lighting. The magma was at the bottom of a hole comprising the majority of the chamber, stretching circularly from one wall almost to the other. This area was where the Dark Man was to be confined until the end of time, in a place where there was no way to track time, no escape from the sweltering heat, and no ground for him to rest on, for the barrier keeping him here ended just at the edge of the basin. But everyone knows how the devil can fly. He could not sit and rest, but he had his means of suspending himself in the air. Unfortunately, there was no way to steal his magic way from him - only to create a wall against it. The Light-Haired One had been kind enough to leave a crescent-shaped sliver of flat rock left between the wall and the Containing Basin. just in case someone desired an audience with the Scourge of the Earth.
raising his right hand to the wall, the stone wiggled and churned, like some kind of liquid. it began to melt and sink into itself, revealing that it was in fact a carved door bearing a remarkable glyph. The glyph - for so complicated was it that the simple term "rune" could never suffice to describe it - glowed with the same light-blue energy apparating throughout the cavern. It began with the man's hand and flowed ever outward, the carved-out glyph acting as a trough, filling its own channels and guiding the energy into six outer lines ending at the edge of the door. When the bluish light reached the finality of its course the lock was complete, liberating the door to split down the middle and it's two panels to slide apart. They remained open for a mere quarter of a minute; up until the magic powering the device ran dry and forced the return of it's former state.
All this the Dark Man watched. Forget the acrid stench of burning flesh and dark magic. Forget the unbearable heat in this forgotten hollow. Forget his goal, his plans, his ingenuity being snatched before him and proven false - forget all of those things! There was his man, there was the criminal! Walking calmly away with naught but an injured arm! Was that all his power amounted to?! There went the Imp who had stopped him and lived! The wretch SURVIVED!  He, the Conqueror of the World and Master of Darkness, had tasted victory, and this cretin had stolen it away before he could even bite! And now the Dark Man was defeated. Locked away, but never to die - no, he could not die! - while his would-be executioner slithered past magic doors to safety! He was safe! The bastard had won! HE WAS STILL ALIVE!!
The Dark Man's mind began to twist. He could feel his anger, his hatred, like thick ropes inside of him, slipping between each other within his too-full body. But mostly he felt the heat. He felt a fire in his chest, first small and hot like a match, but growing. So fast it was growing. Feeding off the twisting ropes that were his innards. It was no longer a match, but a candle. Not just a candle, but a lantern. No longer a lantern, but a torch! And now the torch was a raging fire, an inferno that could not be contained! It swelled to the point of bursting through his body, devastating his mind and consuming him so completely there was nothing left but rage, refined to the core by this towering blaze.
                  Only the purest rage.