Our hero Finn The Human is in the tree fort. His best buddy Jake glides in through the window.
Finn: "Hey Jake, how come you're flyin'?"
Jake: "Lady Rainicorn taught me"
Jake: "But never mind! That jerk The Ice King has teamed up with some Battle Cubes and Ghosts and is coming to kidnap some princesses!"
Finn: "Lemme grab my crossbow! Let's stop him!"
The two fist-pound then Finn hops onto Jake's back, crossbow in hand, and together they leap from the window to battle.
. . . or something like that.
Play with the arrow keys and space.