y'all know how Darwin used to study evolution and such. in one of his studies, he discovered a group of birds (and I am paraphrasing bc it's 2am and icba find sources rn) native to one place got swept away in a storm and essentially got redistributed onto another place. the food and wildlife being different in the new place, the birds had to find away to survive, and through trial and error (i.e. evolution), they basically mutated/evolved to survive the new place, which took years
the point i'm trying to make is that it does not make complete sense to me that Grimmel managed to single handedly wipe out all of the fury family of dragons (night furies, light furies, etc.).
the fury family of dragons (FFoD – i'm being lazy, sue me), must've AT LEAST been native to a land elsewhere. this could be the Hidden World, or literally anywhere outside the archipelago, and a small number of these dragons got swept away to where Grimmel could reach and kill them.
we already know that dragons cannot fly for extended periods of time without rest. so it's *possible* that some of the FFoD got separated from the rest of them. anyways, that's my two cents on this

















