It resided in valleys, which is unusual as dragons typically reside on mountains. It was generally considered one of the most beautiful dragons, with pearly scales that line its body, and glittering multi-coloured eyes that have no pupils. The Opaleye's eggs were pale grey and have been known to be mistaken by Muggles for fossils and its flame was vivid red.

The Opaleye was not particularly aggressive, rarely killing unless it was hungry. Its prey of choice was sheep, but it has been known to attack larger animals. In the 1970s, several kangaroo killings were thought to have been caused by a male Opaleye that had been ousted from its territory by a dominant female. It is a class XXXXX.