Meet Jalsgrim Redmother...or was it Jarble Toothface? Or Tim the Enchanter? Eh, ask him his name and you might get a different answer every time.

Jalsgrim was created in 2e and eventually ported to 3.5. I've played various incarnations of him with different DMs (few let me keep him around for very long). Jalsgrim is native to Limbo and his head is permanently wreathed in purple flames that shed light as a torch (this effect is present regardless of which form Jalsgrim takes, much to his annoyance).

A more-detailed Jalsgrim background:
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The poor son of an orange and a tribe of gnolls, life was hard for Jalsgrim growing up on the spaghetti vineyard. Fortunately, he was born at a young age so he got an early start at life. Then the giant gad flies.

When he was just a little boy, the vineyards were burned down by a horde of marauding chipmunk barbarians, who killed Jalsgrim's parents and sold him into slavery to a bunch of elves who forced him to work in their pork mines. They forced him to work all day in the mines and he had to fight with the other slaves over every piece of lumber the elves gave him to eat. Fortunately, he was bigger and stronger than most of the other slaves, considering most of them were gnomes and kobolds. It wasn't long before they elected him their leader and taught him how to use their ancestral weapon - the waraxe.

Shortly after mastering this weapon, Jalsgrim lead the slaves in a revolt against their slavers. Unfortunately, he was the only survivor and was forced to eat his way out of the mines. But he had a fondness for bacon so it only took him a couple days to make it to the surface.

He wandered for a while, alone, before encountering a wandering monster - a human wizard. The struggle was nearly epic, but Jalsgrim eventually defeated him and claimed his pot of gold and spellbook. Jalsgrim immediately set about learning the intracacies of magic so he would never be caught unprepared again.

Although he had a tough time making sense of the writing in the spellbook at first, magic came naturally to Jalsgrim - especially transumations. It wasn't long before he had mastered a few cantrips. Soon after, he learned how to turn himself into a little girl. He vowed to never use this newfound power unless it would be really fun. Later, he learned how to transform himself, and others, into different creatures as well.

Jalsgrim journeyed for a time with some other people, mostly killing monsters and that sort of thing. During his travels, he learned how to unleash blasts of pure, undiluted magic with unpredictable effects - often turning the tide of battle at crucial moments. His companions were quite pleased with this ability. Unfortunately, since he had become so powerful so quickly, his companions felt that they would only hold him back from obtaining even greater power. The cheered him on as he left, waving and saluting him with their weapons.

Sometimes when fighting or just mucking about, Jalsgrim would use his power to unleash undiluted magic - only to find himself instantly transported to completely different places, sometimes even to completely different planes of existence! After one such transportation, he found himself in a strange place with violent elemental storms and giant frog people constantly chasing him around. It was great fun and he decided that this place would be a perfect place to make his new home.