raven,Knowledge and vision
the crow bring death and destruction

Euron Greyjoy has two eyes
his blue eye laughs in the light, he is a good pirate, generous, he takes a very small share and gives the booty to his crew, he wants the best for his people.

but this is just nonsense, actually, Croweye
he is quite dark and cruel, he hides his darkness with the goodness of his truths, like the eye he hides.

abusing his own brothers as a child. the fact that his crew consists of mutes, capturing wizards who make a drink that shows magical visions, baiting a wizard to others, being able to go to cursed places, having items that can bring doomsday makes him a very dark character