Naga Royal Guard

The Naga Royal Guard is a Naga unit.

Naga royal guard, as their name implies, serve as protection for important individuals.

Speculation
They are believed to be a magically-enhanced strain of Myrmidon. It helped both Illidan and Vashj in their efforts.

Even though the Naga society is female dominated with mainly females studying magic, these creatures are by far the strongest units in the naga army possessing both immense physical and magical power. In the game, (Warcraft III) they were so powerful that players considered them on an equal footing with Hero units.

Statistics from Warcraft III

 * 1350 HP
 * 500 MP
 * 47-59 chaos melee damage
 * 5 heavy armor
 * Abilities
 * Frost Bolt (ranged stun and damage)
 * Crushing Wave (line damage)
 * Resistant Skin (reduces effect of negative spells on this unit)
 * Submerge (goes underwater to avoid attack)
 * Summon Sea Elemental (summons Sea Elemental)