Part of PONIES: The Anthology V https://youtu.be/Z0LgI6nF0rM

Source video:
My Little Pony: Friendship is Magic (S4 E4 "Daring Don't)
BattleBlock Theater

Source audio:
My Little Pony: Friendship is Magic (S4 E4 "Daring Don't)
BattleBlock Theater "Secret Area"