Shadow Bulblin
This is the Twilight Realm equivalent of a common enemy encountered in Twilight Princess, the Bokoblin. Due to Zant and the Shadow Beasts stealing the light from the provinces within Hyrule, it caused a transformation to the enemies.
This version of Bokoblin deals the same amount of damage as the original (1/4 damage), they also act very similar. The only notable change in this version is in appearance. They are around the same height and build as their counterparts but they have a black color scheme and have what appears to be a white mask. However they do wield a different weapon than the original Bokoblins, instead of a wooden sword they now have what seems to be a black club.
As Link will be in Wolf form when encountering the Shadow Bokoblins, the combat techniques may differ. The most effective way to deal with these enemies is to use Midnas power field ability, however the jump and spin attack are also very effective.
Gallery
Shadow Bokoblins in combat in Twilight Princess