Prongo

Prongos are enemies that appear in Super Mario 3D Land, named after the word prong. These enemies have a large, metallic blue box object with golden spikes sticking out along the sides and the top. The spikes have orange markings surrounding them. The metallic blue box covers the majority of their body, except their green feet and yellow underside. Prongos have small red eyes that peer through a hole in the metal box covering them.

Super Mario 3D Land
Prongos appear in later levels of normal worlds, but become common enemies in the Special World. When a Prongo spots Mario or Luigi, it will run after them. If the Prongo gets close enough, it will dive and try to headbump the player, similar to Headbonk Goombas from Super Paper Mario. If the Prongo misses, it will become stuck in the ground due to its spikes, leaving it open for attack. After a few seconds, the Prongo will free itself from the ground and continue its pursuit on the player.

Prongos cannot be defeated when they are rightside-up, except with the use of a Star. Tail whips will flip a Prongo over, making it vulnerable to any attack.

Trivia

 * Prongo's attack and defeating methods are nearly identical to that of the Snooze-A-Koopas from Super Mario Sunshine and Flaptacks from Super Mario Galaxy 2 as they all flip in the air in attempt to hit the player, get stuck in the ground if the attack misses and are only vulnerable on their underside.