Muths are enemies that look a lot like mammoths and are found only in Chapter 5-1 in Super Paper Mario.
They have 100 HP and an attack of 5. You get a lot of points for defeating them, so you should. The best way to defeat them is to use Bowser's Flame Breath on them. They have stronger versions of them called a Mega Muth and a Dark Muth. Muths sometimes drop a Bone-In Cut and it's the only way to let one.