Fat Cat is a unique shoot 'em up with puzzle elements. You control an owl and a fat cat simultaneously with your mouse and keyboard. The owl can shoot enemies, slide blocks, press buttons, and drag the fat cat. The cat doesn't do much except eat cake, but when it eats enough, it can unleash a powerful burp that kills enemies and destroys certain types of blocks. The owl is invincible, but the cat will lose health if it touches an enemy.