Had Thoughts (tm) of the old Murderburd thing, about potential redesign of the birdmonsters.
Having gone through what-ifs of huge dogs, dinosaurs, dragons, pterosaurs, owlbears and giant lynx-type cats, and none of them felt quite right, I briefly wntertained the idea of wingbeans, but the trolls didn't feel enough like "small cute pet" people instead of "large hunting animal" people. But what if something wingbeany, but big?
Also vestigial arms.
(I want to call the species "aarnivaris", as a sorta play on words with aarnikotka, Finnish for griffin, but I don't think that would translate back into English. Aarni is an ancient word for a spirit being or guardian of treasure, kotka means eagle and varis is a crow. On the other hand, Murderburd does not translate into Finnish without losing all the fun from the pronunciation, so *shrug*)