Death is not really it's theme though. Even if it does kill an awful lot of people.
Think Evil Draconic Divinity of Life/Growth/Fertility with sub-portfolios in Magic and Learning.
Natural Selection is a thing that is strongly tied into Life and Growth though, so it does have a claw in the Death portfolio by association. Which brings us back to how it kills a lot of folks.
I mean, Dungeons and Dragons has stuff like Ragnorra, and the works of Lovecraft has Shub-Niggurath, or Marvel with the Cancer-verse and the beings responsible for it...or, you know, Nurgle, and a bunch of other examples of not so nice Life-centered entities that can get pretty bloody horrific.
Notably, the Night Fury form is a very convenient size for a number of purposes, not too big, not too small. Such as allowing it to fit into buildings without going through the effort of warping space into a pretzel. So it's one of the better options for an avatar as far as it is concerned. Though it does also use other dragon related forms when convenient.
It's a pretty nasty critter all things considered, even if it's only the third most powerful character i have come up with (To be fair, the second and first on that list is a Living Multiverse benefiting from exponential "Stronger than the sum of it's parts" fusion bonuses and the Collective Evil of all Intelligent Life Across Multiple Multiverse Clusters Made Manifest respectively)