Reaplings

From Zelda Wiki.org

Reapling
Game(s)	Phantom Hourglass
Habitat(s)	Ghost Ship
Effective Weapons	Bow (Stun Only)
TWW Spoils	None

Reaplings appear in Phantom Hourglass, when Link makes his way on to the Ghost Ship. Reaplings, unlike Phantoms, deal two hearts of damage to Link and do not knock him unconscious.

Reaplings can be avoided by only moving when they have their backs are to Link. Unlike Phantoms, Reaplings can move and see through walls. They are immune to most forms of attack and cannot be killed, but a shot to the back with an arrow will temporarily stun them.

They seem to be subservient to the Cubus Sisters, since the Sisters initially tried to leave the task of dispatching Link to them, and were later disappointed when they failed.