Angels of Death, Angels of Valhalla.
Valkyries are more-or-less the Norse version of angels of death, except significantly more badass in their job description, in their physical aspect, and in what they represent. According to the Encyclopedia Britannica, they are the maidens of Odin who walk along the battlefields of men and choose from the slain those who are worthy to enter into Valhalla.
It is interesting to me that Odin does not do the choosing himself, but rather he entrusts this job – a job that means the difference between eternal joy and misery for the dying – to women. Unlike the angel of death from Christian mythology who seems to follow the directions of a higher being, the Valkyries are allowed to do as they want, killing and denying rewards to those they dislike while protecting and rewarding those they do. And so these maidens decide the eternal fates of men.
Valkyries appear in mythology both as purely supernatural beings and also at times as some demigods, and so I frequently imagine something that looks less like an angle more akin to a Viking shield maiden, specifically Lagertha from the History Channel TV series Vikings. She is a fierce fighter, a loving mother, and one of the most fantastic female warriors ever seen on television. She protects those she loves like a mother bear, she is unfazed by adversity of any kind – whether it be the near-starvation of their city or the betrayal of her trusted friend – and rains havoc down on those who wrong her and hers. If I ever had a Guardian angel looking over my shoulder, I would want it to be her.
Valkyries – due to their half or full supernatural powers and their serving of Odin – represent both the power of a god and of women. Unlike in Christian mythology which tends to gender both God and the angels as male and gives the powers of life and death to their god, in Norse mythology Odin gives the power of deciding who dies and who lives to his women warriors, as if he knows they have better instincts about who is worthy of Valhalla. This seems to me to be an empowering image, and reminds me of the Amazonian warriors, who need no men to organize and order them around.
Valkyries are the embodiment of life and death in the beauty of the female form without any allegiance either to men or any god. They are the ultimate warriors, and they will take you to Valhalla.