Gronvaenga
From Wulfgard Wiki
A truly ancient dragon of Midgard, the being known to Northmen as Gronvaenga is the green dragon who guards Mimiriholt, the eternal forest. Of the tales about guardians of this forest, such as elves, defending it from woodcutters, none strike fear into the minds of those who would encroach upon that land so much as those of the great green-winged beast swooping down from on high to burn them to ash, and then blasting the land with green flame to heal the damage they had caused. It is said she is friends with the elves who live there and is one of the wisest creatures in existence, but seldom does she venture far from the forest she protects.