From the Super Mario Wiki
“Hoo hoo hoo hoo hoo hoo! You're gonna be coleslaw, kid! And that ain't good!”
Bristles are spiked monsters made of rock and are found in the game Paper Mario: The Thousand-Year Door. Similar to Clefts, Bristles have spiked tops, high defense, an immunity to fire attacks, and can be flipped over by an earthquake or an explosion. Unlike Clefts, Bristles do not lose their top-spiked defense when flipped and are also immune to close-range attacks like Gulp and Mario's Hammer, as their large side-spikes pop out to protect against approachers (even when the Bristle is asleep).
Despite their copious defenses, Bristles have very low HP and are easily taken out with POW Blocks, Earth Quakes, Superguard, or Earth Tremor. Mario is also capable of simply hammering them should he have the Spike Shield badge equipped, though without Power Smash, Piercing Blow, or the Ultra Hammer it will do no damage.
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