So there is not Healing Power, but the gods gave 1 special pup the Healing Power.
Spirit World Lore
When Wolves die, they go to the Spirit World and our spirit will rest forever. Also, they can become more powerful.
Power Lore
The Gods thought it would be a better chance of survival for the wolves. Also they can become more powerful.
God Died Lore
The gods are basically immortal, it is so dangerous for the gods to go down on earth. If they die on earth they don't regenerate, they are dead forever.
So if they die the elemental power they had wouldn't be existing on earth. So if the Water God dies everything that water is gone from earth, there would be no water at all.
Shadow Powers Lore
So when shadow got his power the Dark power his eyes change from a light pinkish red, to a dark red he was never the same once he got his power.
It turned him into a monster, and killing a lot of wolves. But he never wanted to actually hurt anybody. But his power drove him mad.