Wir'lovel Repense.
While the character started at first as a GM-controlled villain in an Ironclaw game of mine, the character evolved into something so much better. The players immediately took a liking to him as a villain, despite his direct opposition to the party. Suave, debonair and cunning - never fighting directly, working through minions or legal action than by force or magic. In fact, the character was not a magic-user: he was a completely political character. The times he had 'caught' the heroes, his "honor" would implore him to reveal his scheme and leave them to figure a way out on their own... always coming a bit ahead, even when defeated.
While this campaign finally reached it's end, Wir'lovel using a dark spell he did not know how to use to save the kingdom... at a great cost. The spell was necromantic in nature, he was expelled from the continent, and thus: out of the game. The spell did more, though: channeling the necromantic energy for the spell had ended his life - he became a lich, and his stagnant mind slowly went mad.
On another continent, in another game, he became my character. His political aspects tempered with necromancy, his silvered tongue and handsome, still-living appearance got him a good amount of respect... and a few lovers, of both genders. He rose quickly to the rank of advisor to the place's archmage... twisting rumors in his favor... winning friends and allies among the mages, thieves, warriors, and workers of the village... ever-ready and eternal to make his strike and work towards his true agenda: To purge the world of stereotypes, to change the thoughts of the people towards respecting the mind instead of the body, to bring forth a new era of magic and knowledge... and slaughter anything that got in the way of his 'dream'.
It was a slow slope, one which I was able to play out his every fall towards his "well-intentioned madness". I loved the character very much... the game ended, sadly. Wir'lovel himself was finally ended after a successful coup, shot through the skull with an arrow forged from the bone of a dead god.
However, his legacy lives on: both in my characters descended from him, and as the Demigod of Deception in one places' world.