Bristle

Bristles are enemies featured in Paper Mario: The Thousand-Year Door.

These deadly creatures are found only once in the game. They are located in the dark reaches of Shhwonk Fortress. While Mario is wandering the halls of the fortress, he comes across this room, with two of these machines. They attack Mario. After this fight concludes, Mario will never be able to battle a Bristle again. This fight must also be completed in order to pass through.

In a battle with these monsters, if Mario or his partners goes in to attack with a hammer or any other attack like that, a Bristle will activate a hidden blade, cutting those who come too close. With the high defense and spikes, Bristles make an above-average foe, however, these creatures can also be flipped upside down for two turns, thus revealing their unprotected underside.

These creatures have a much more powerful version as well, the dreaded Dark Bristle.