Born into a human family of fighters as Derrick Wulf, he was brought up in a household of hammers, swords, and axes. His family was renowned for their undeniable prowess, and they were set on having him follow in their footsteps. Win after win after win, this lifestyle was that of valor and pride.
It was crushing. Every missed hit was a disappointment, every wrong step a vicious insult; imperfection would not be allowed under any circumstance. So, Derrick attended his small town's tournament that happens only once every decade, which made it quite the momentous occasion. He had win after win after win, and at his last fight--the fight that would have won him gold and valor--he was absolutely demolished. A few cracked ribs, a shattered shoulder, a dislocated knee, and a family that no longer housed him.
He was homeless, in searing pain, and out of a future that was robbed from him. He fled shamefully into the woods, hoping to find something; anything that would give him hope and pride. Alas, all that was found was a pack of feral wolves that seemed to find the wounded Derrick quite easy prey. His chances of simple hermeticism were taken away, and as he was bitten and clawed, he screamed a damnable scream that seemed to push the ravenous wolves away, but helped him quite little.
He was left in the dirt in the middle of a sea of trees, laying in a pool of his own blood. In a blind fit of desperation, he uttered the words that would change him forever.
"Asmodeus, King of the Nine Hells, I give unto you my soul and my undying faith, and ask of you to make me anew."
The ground rumbled, and he seemed to be yanked upwards by some magical force into the air. The earth rumbled and nearby life seemed to wilt and die.
And from below came a low, resonating voice.
"You shall bear my mark," and thus his skull fractured at the temples and bore the horns of a ram. His spine had every vertebrae shatter, one after another, and the bone shards had to rend through flesh to form the large tail of five feet, before snapping sinew to contort back into the cylindrical shape of the now much larger, extended spinal column. The exposed spine seeped out skin and muscle, forming the thick tail. "Your skin shall be stained with an unforgettable memory," and thus blood tore through his flesh as if it were daggers and needles, before fusing with his skin, turning it a maroon red. "You shall be blind without faith, and trust in me to guide you," and thus his eyes twisted in unnatural ways in his skull, losing every feature as it became devilishly deformed. All that was left was, in each socket, an eye with naught but a waxy sclera.  "You shall speak my tongue," and thus his mouth burned with an unholy flame, his tongue having abyssal etchings carved into it. "You shall bleed my blood," and thus his heart pounded as an ethereal claw carved into it with a single swipe, before forcing into it a black, viscous ichor. "You shall know my arcane secrets," and thus his right hand was branded with searing flame, putting onto his palm an irremovable mark. That of the Eye of Asmodeus. "You shall be born anew, your mortal flesh reformed," and thus his wounds suddenly had the searing of white-hot pins thrusting through them, performing a sort of sacrilegious surgery, which healed his wounds. Suddenly, the presence of Asmodeus disappeared. Silence fell as quickly as Derrick fell to the ground. He was in great, terrifying, pain. He tried to stand up, but crouched over as he suddenly developed a splitting headache. Tears fell to the ground as he yelled out in pain. "Who am I?!" His mind pulsed, and from the depths of his soul echoed the voice of Asmodeus. "You are not Derrick; he is dead. You have shed your former self. You have been strengthened by your pact, my child. In return, you will meet my demands. You will learn more at a later time, but for now, you must make a grave for your former self. You must, for if not, you cannot be born anew."
His mind went silent. The silence was welcoming. As the presence of Asmodeus left, so too did the pain that was brought on by the king. So as the warlock created a grave for who he was, he was becoming more and more confident to live the new life he was given. The life he had always dreamed of. The life of Victory.