Some attributes
First Master of Illusion, member of the Shadow Trio, serving as the "Two-Horned"
Second Can vanish and re-appear
Third known as the Herobrine in an alternate Universe
Other attributes

Terdaka, master of illusions, and Two Horned beast, is a villian in the Cartoon Universe, he serves as the Shadow Creature who controls Nightmares, he is also known as Herobrine.