"Son of Rap Bear" is the third episode in the ninth season of Adventure Time. It is the two hundred sixty-ninth episode overall.
When Flame Princess is coaxed into a high stakes battle against the indomitable Son of Rap Bear, Finn must help her search for a new strategy.
- Jake (non-speaking)
- Rap Bear
- Marceline (cameo)
- Princess Bubblegum (cameo)
- Bun Bun (cameo)
- Kim Kil Whan (cameo)
- Turtle Princess (cameo)
- Starchy (cameo)
- Blank-Eyed Girl (cameo)
- Banana Man (cameo)
- Wyatt (cameo)
- Breakfast Princess (cameo)
- Toast Princess (cameo)
- Crab Princess (cameo)
- Elder Plops (cameo)
- Flambo (cameo)
- Candy People
- The rapping chipmunk that performs for Flame King is voiced by Open Mike Eagle, who also happens to be the co-host for an Adventure Time podcast called, Conversation Parade.
- When Flame Princess sings "climb a rock," she appears to be actually climbing an insect husk, which is very similar to the shells of Ohmu from the manga and film Nausicaä of the Valley of the Wind.
- Rap Bear lives inside the monster from "Belly of the Beast."
- Flame King and Bun Bun still live in their chipmunk cave from "Bun Bun."
- Crab Princess makes an appearance for the first time since "Breezy."
- Dr. Dextrose makes a cameo appearance in this episode. He has not been seen since the season 2 episode "The Real You."
- A blank-eyed girl from the episode of the same name makes a cameo appearance.