Vaatu the spirit of darkness and chaos,(The legend of Korra )

Vaatu is a Eldritch hell kite that shoots lazers . It's raw esoteric duality nonsense that just makes him look cool . Most spirits in avatar either have a animal form or something you can at least make out as a solid shape .

Vaatu as a primordial chaos spirit who only wants to bring about darkness is almost flat like a bacterial creature . His entire body is almost see through. His symbols unlike Raava give him the look as aneomba with a hellish ribcage .