Cast[]
- Beowulf as Finn
- Grendel as Princess Bubblegum
- Grendel's mother as Ice Cream Lady
- King Hrothgar as Donut Guy
- John Malkovich as Jake
- John Malkovich as Beemo
- Wiglaf as Starchy
- Queen Wealtheow as Fionna
- Ursula as Cake
- Hondshew as Duke of Nuts
- Garmund as The Ice King
- Young Cain as Jermaine
- Adult Cain as Chet