Undergrunt

Undergrunts are mole-like enimies That appear in Super Mario Galaxy and Super Mario Galaxy 2 in the galaxies Gusty Garden Galaxy (SMG) and Battle Belt Galaxy (SMG2) making Undergrunts quite rare.

Super Mario Galaxy
In the game Super Mario Galaxy Undergrunts appear in Gusty Garden Galaxy in "The Dirty Tricks of Major Burrows" as uncommon enimies only appearing on two planets. You cannot do anything to the Undergrunts while they are tunneling in the ground because of their helmets. They can be defeated by ground pounding the ground near them to pop out the Undergrunt. Then the player must spin the enemy while it is still out of the ground.

At the end of that level there is a boss extremely similar to an Undergrunt in appearance, Major Burrows, and is defeated in a nearly identical way.

Super Mario Galaxy 2
Only three undergrunts appear in Super Mario Galaxy 2 on one planet in Battle Belt Galaxy. They are deafeated in the same way with no changes added.

In addition, Major Burrows appears again in Boss Blitz Galaxy.

Appearance
An Undergrunt's appearance is similar to most mole like characters (Monty Moles, Rocky Wrenches etc.). They have dark brown fur, and light brown bellies, noses, and cheeks. Undergrunts also have yellow spiked helmets preventing the player from stomping or spinning the mole. This is the only indication of an undergrunt beside the fact that they leave a dirt trail behind when they tunnel in the ground.

Trivia

 * Besides the helmet, undergrunt have the exact same appearance of a Rocky Wrench.
 * Although they are listed as enemies in the offical PRIMA game guide for Super Mario Galaxy and Super Mario Galaxy 2, Undergrunts are not listed in the Mariowiki list of enemies (as shown below)