Tree of Life (in these myths) is Yggdrasil and there was a bit of action on that word a few weeks ago. I'm really not sure how to categorise the functionality of cadaver sucking. Dung Beetles Of The End Of Time does have a ring to it, so nidhoggrs have a least one good band name in them.
I have a vague memory of hearing about this once. Isn't it true, despicable as the action sounds, that eating the dead at the end of the world is performing a valuable and needed function? What I mean is... do the tellers and re-tellers of these myths don't tell them as if the nidhoggr is some kind of mean bogeyman, but more like a necessary balancer of the cosmos?
Icelandic, cognate with Swedish nidhogg. In Norse myths, the "gnawer from beneath," the serpent which gnaws at the roots of the Tree of Life. Nidhoggr is also the devourer of the dead who sucks cadavers at the end of the world.