Horzy eats his food, but he sees mystery juice. Cat sees it too. Then, Horzy's bowl becomes the mystery juice. He drinks it and becomes a box. When Cat drank it, he became Horzy's bowl. All of a sudden, Horzy started disappearing and became a vertical line. Next, the juice drank herself and became the bowl, making Cat and Horzy normal.
Play the game here: https://scratch.mit.edu/projects/1261581912/