He was the last Guardian and one of the most influential people in Azeroth -- but he never meant to be either one. Of all of the myriad and varied heroes in World of Warcraft, there is one man who is responsible for the majority of the events we see in Azeroth today. This man was solely responsible for the presence of orcs, responsible for the Horde, responsible for the ever-evolving conflict between Horde and Alliance. He was responsible for the original destruction of Stormwind, for the death of Anduin Lothar, King Llane Wrynn and many other heroes whose exploits didn't make it into the annals of history. He was responsible, indirectly, for the corruption of Arthas and the subsequent death of King Menethil, the razing of Stratholme and the rise of the Scourge. He arguably has more blood on his hands than any other being in Azeroth.
And yet he was also responsible for the first tenuous threads of peace stretched between Alliance and Horde. He was responsible for the rise of some of Azeroth's greatest heroes -- he was the man that made Varian Wrynn who he is today, he was the man who turned Thrall from an orc with dreams of peace for his people into a leader of action. He was responsible for saving Azeroth from being razed and torn asunder by the Burning Legion. He was a man of many talents, and a man of many regrets. His name is Medivh.