Bat Pig only appears in cave levels on The Road to El Porkado. It’s eyes are only seen unless you use a Night Vision Goggles Powerup or the alien variant for the Lamp. Bat Pigs can carry a Star Box which gives you a Star, TNT (only in Level 6-7) and a metal box (which uses to interact the Gates and Buttons). Bat Pigs can also carry nothing. When they disappear they leave a few smoke clouds.