The Ice Queen is a boss from the game Golden Sun: Dark Dawn found within the Harapa Ruins. Once she is defeated you gain the Ice Queen Stone which, when equipped, enables Cold Snap psynergy, which is only available to Mercury Adepts.
Her apearance is that of a woman with pale skin which is tinted blue presumably to denote her icy nature and power. Her hair is grey indicating her age and she wears a golden crown, two golden earings, a purple and whit robe with a white fur collar and an icy blue cape.
Her main weapon is a large blue magic staff with thre pale blue crystals atop it in a trident like fashion.
The Ice queen role in the game is relatively small but we are told after winning the boss fight that she tricked Nyunpa into bringing her to the Harapa ruins from Passaj, she then turned him to stone and kept him she should need him to move her as she is bound to the Ice Queen Stone. After she is defeated, the curse on Nyunpa is broken, and he becomes human again.
She refers to Harapa ruins as her "Chilly court" possibly hinting that whilst she was alive she lived in the Harapa ruins.