Ice King (formely known as Simon Petrikov) is the main protagonist of the series Adventure Time .
Before the Great Mushroom War, Simon was a human before he became the King of Ice he was smart, with olived skin, glasses, dark-haired and a suit. He is an antiquarian, In the episode I Remember You he was the one who discovered the Enchiridion at some time. During or after the war he purchased a gem crown or (Ice Crown) when he had weared it in his head it had a huge strange effect of it. It frighten his fiancee and never saw her again. The crown turn his eyes white and all the things that made him the Ice King.
After the war he saw Marceline in a rumpage city duo to the war. He gave him Hambo and they also bonded at some time. It could be implied that the crown he wore only sought to protect him. It taught him the secrets of the "ice and snow," so he would survive the Mushroom War, as it did for Farmworld Finn in "Finn the Human."
When the transformation was complete he can't remember anything of his past even about the war. He was no longer a human. Before he became the Ice King, he believes that his fiancee and him will see again very soon.
Currently he is interested in capturing princess and always Princess Bubblegum.
Ice King is a short, blue, elderly man with unusually pointy fingers, pointy toes, sharp teeth, and a goblin-like nose. He wears a dark blue tunic and has a large white beard that covers most of his body. Though the robe gives him the appearance of a larger man, Ice King's body is in fact exceptionally thin. Despite this, Ice King reveals that he is on a diet in "What Have You Done?" Ice King is rarely seen without his crown; without it he is powerless and he is revealed to have a short length of white hair atop his head. The only time he has been seen in shoes was when he was working out before Slime Princess came to talk to him in "Loyalty to the King."