Truly one of the most bizarre seemingly native races out there. It was confirmed they aren’t demons, but they 100% look like Imps. It’s not a simple case of model reuse with no lore implication whatsoever, since their important similarities have been officially acknowledged in quests like this one https://wowpedia.fandom.com/wiki/Breath_of_Mist
.
Back in Legion, an Imp NPC named Daglop even said :
There is a legend that some of our ancestors can be found on this world that are not part of the Legion. I bet they are boring.
They also resemble Goblins (and arguably Trolls, but especially Goblins) a lot ; the Goblins being one of the races with the most obscure ancient origins. The only canon information we have is that they are the result of the kaja’mite experiments conducted by Mimiron on a “small primitive race that roamed around the forests near Ulduar”, which is funny to me because Goblins are the last race I would associate with forests, while Grells are absolutely depicted as creatures of the foret (even as “forest spirits” occasionally).
It’s been hinted at that Aessina may have created the Grells, which sounds perfectly reasonable, but it also… doesn’t really explain why they resemble Imps and Goblins so much. At the contrary, it would imply that Grells and Imps are completely unrelated (since Demons first reached Azeroth as “late” as 10 000 years ago), which would come off as very weird.
Barring the Aessina theory, I guess it could’ve gone this way :
A long time ago, potentially before the creation of the Burning Legion, a group of Imps, that is to say a race native to the Twisting Nether, ends up accidentally crashing down on Azeroth for some reason → Over time, they adapt to their new environment and due to lack of exposure to the Fel and all the unstable energies flowing through the Twisting Nether, they lose all of their Demonic features, including the ability to be reborn in the Nether → One day, Mimiron takes a bunch of forest Grells and infuses them with kaja’mite, creating the Goblins.
Goblins being related to Pygmies (the canonicity of which is questionable, by the way) doesn’t conflict with this theory : the Pygmies would merely be descended from the Grells who didn’t undergo any of the Mimiron experiments.
Idk. Grells are just weird. Thoughts ?
(Just to make things clear, I have no doubt that the model reuse had no lore implication INITIALLY and that’s just something the devs did because why not. Now though, the matter does need retrospective lore explanation)