Zatch Bell! S01 E109 Duel in the Northern Country. Fated Rival. Umagon Frozen!!

Sunbeam is told that he must go to Hokkaidō for a week of training so he leaves his Mamodo Ponygon with Kiyo and Zatch. Zatch seeing how badly Ponygon wanted to go with Sunbeam helps Ponygon sneak aboard a plane to follow Sunbeam.