An alien pod crashes onto Earth, revealing an equine alien named Party Horse who's on the run from his history teacher.
Tropes that apply to this episode:
- Disproportionate Retribution: If Party Horse fails his test, Professor Party Horse will blow up the Earth.
- Earth-Shattering Kaboom: Professor Party Horse threatens this for Earth if Party Horse doesn't pass his test.
- Ironic Echo: Benson chides Mordecai and Rigby for their slacker ways, but they ignore him. However then Party Horse likewise keeps slacking off, the two use the same word Benson told them.
- Lazy Bum: Taking just one test to be allowed to party for the rest of your life is apparently too much work for Party Horse.
- Planet of Hats: Party Horse's planet is inhabited by horses who dedicate their lives to partying.
- Planet of Steves: Everyone in Party Horse's planet is also called Party Horse.
- Sadist Teacher: Professor Party Horse. Not only does he try to have everyone on Party Horse Planet see Party Horse fail, he does whatever it takes to make sure he does even though that if he does he'll destroy the Earth and everyone on it.
