Eir
Eir is one of the most unknown North
Eir is one of the most unknown North goddesses - even in Edda there is a very little information about her.
All we can say - she was one of the nine Menglod maidens and only Eir Aces accepted as a goddess, equal to them. For what? Oh, this is simple.
Eir is a healer, a powerful one. Everyone in the Asgard knows - if you're wounded, go to Eir, if you're sick and feel weakness - come to her and she will heal you. Eir's healer powers are very important to the Gods of Asgard, because most of them are warriors and can be wounded in countless battles.
Asatru say, Eir won't heal you just because you sick. You must prove her that you want to live and only after she'll test your spirit, only then she'll help you.
Eir is merciful, but she is some kind of a warrior too, like all the Northmans and Aces.