Backstory...

An impetuous young orc, Nihlothak was anything but ready for the responsibilities forced upon him at an early age.  The world of Draenor now known as "Outlands" always boasted a myriad of dangers, despite its beautiful nature.  However, his people had always overcome each and every one of them, forging a sprawling shamanistic civilization that cultivated a new age for the Orcs.  When the peaceful Draenei arrived on their world, his small village nor the rest of the orcish peoples could have possibly imagined the horrors and evils that would soon come. 
Nihlothak had displayed an affinity to the elements early in his life, and showing wisdom that garnered him praise.  Unfortunately, this success at such a young age gave him an overconfidence that landed him in constant trouble.  He was very interested in the Draenei people, always the inquisitive one.  This interest led to a friendship with a young Draenei for many years, and even more peaceful relations between the two races.
A few years later while little "Nihl" was still young his father and chief of his tribe was summoned by the High Chieftain to a tribe meet, his father never returned.  Two days later, the Orc's declared war on the Draenei.  It was obvious that Nihlothak would pick up the mantle his father had left behind, and so he did.  Civil unrest and skepticism was rampant as stories of shamans losing their powers and all new forms of magic began to arise.  One year later, the High Chieftain Ner'zhul summoned all the leaders once again.
At this meeting Ner'zhul spoke with such a vigor that he captured the hearts and minds of all those present, except for Nihlothak.  He painted a masterful picture about how the elements had turned on them and how the Draenei were the cause, and the only way to save themselves was to turn to an all new form of magic, magic made from demons.  Nihlothak set off to his tent to ready himself for the return home, unsure of what to do.  He was still young and had not the years or wisdom of Ner'zhul, but what his leader was saying made no sense.  Just as he began to pack, Ner'zhul entered his tent and after long questioning and discussion he was able to convince Nihlothak that what they were doing was right.
The next few years were a blur, a haze of blood and carnage, of hate and destruction, that he still has trouble remembering.
He woke up one day, unknowing of where he was or what he was doing.  He looked down at his hands and they were covered in blood.  He looked around and saw nothing but death; men, women, and children, all slaughtered, all innocent.  His eyes filled with tears and his heart with agony.  The next few months were unbearable, never able to forget, never able to sleep.  His mind filled with images, his dreams filled with screams, he couldn't rest until his mind shut everything off.  His powers and any connection to the elements he may have had left, all gone. 
For a few years he traveled, wandering from place to place, escaping slavers and barely holding onto life, until he heard news he never thought possible.  There was a new shaman, a new leader of the Horde who spoke and led with wisdom rather than hate.  A being who promised redemption and a promise of a new future.  Nihlothak set out on a journey to meet this young Orc named Thrall.  Thrall assisted Nihl in finding a new purpose for himself, to reconnect with the elements and serve all of life itself to attempt to atone for the atrocities brought about by his hands.  Nihlothak set out on his journey, and continues it to this day.