|Real name||Simon Petrikov|
|Series||Adventure Time with Finn and Jake|
|Voiced by||Tom Kenny|
|“||I didn't even know we had cable.||”|
Around the time of or before the Great Mushroom War, an antiquarian named Simon Petrikov purchased a crown from a fisherman. As a joke, he put it on his head while showing it to his girlfriend Betty. He apparently did something which made Betty so upset she left him (though it is much later revealed that the man she left him for was his own future self). Under the crown's influence over time, his mind deteriorated until he became senile and crazy. He became the Ice King of the modern era of Adventure Time, the sociopathic, lonely ruler of the Ice Kingdom in the Land of Ooo, who kidnaps various princesses to keep as company and (he delusionally hopes) as girlfriends and wives. This behavior stems from his recalling Betty as his lost "princess." His favorite princess to kidnap is Princess Bubblegum, and he mistakenly believes they are dating. The protagonists Finn and Jake often rescue her. His minions include numerous penguins called various pronunciations of the name "Gunter," Glacial Golems, and Ice Titans.
In FusionFall, the Ice King is located within his fortress outside of Orchid Bay. While his basement and living room can be entered without a mission, the player must have one to enter the dungeons, a couple of which are inhabited by Fusions.
Despite his antagonistic rôle in the game, the Ice King is not a boss and does not seem to be associated with Fuse or any of the game's secondary villains, instead having his own personal agenda of obtaining a wife. To accomplish this, he kidnaps Princess Morbucks and Candy Wife and imprisons them. With the help of Finn, Jake, and Princess Bubblegum, the hero frees the two prisoners. Later, Ice King likewise kidnaps Princess Anna, and it is her sister Elsa and Gravity Falls' Dipper who support the hero in their rescue.
His Nano may be obtained when the Ice King contacts the hero for help, as he accuses his servant Gunter of suggesting kidnapping princesses; Gunter, however, denies the deed. Learning afterward that his penguin servants have disappeared, the Ice King sends the hero to Finn, who in turn sends the hero to a dungeon in the basement. After freeing the penguins, the player discovers Fusion Gunter, the real mastermind behind the "Ice King Invasion." After his defeat, the player earns an Ice King Nano. Since it turns out Fuse was manipulating the Ice King through Fusion Gunter into kidnapping Princesses and Ice King was not acting on his own accord, it seemed possible that Ice King would help the other heroes from then on, thus also freeing Finn and his friends to play a more active rôle in the war. His kidnapping of Princess Anna casts doubt on this.
- His Nano was originally supposed to be a code Nano, but for unknown reasons he received a Level 16 Nano mission.
- There is a T-Shirt based on him that can be obtained by a Secret Snail.
- In his castle there are two doll Nanos: Way Big and Alien X.
- His Nano is the first to be released with a tie-in with a FusionFall Adventure.