So I decided to do something similar with the griffins. After a couple hours of hard thought and sketching ideas out, the most obvious solution came to me: four limbs, back half like a cross between a cat and an eagle, complete with talons; and instead of having both eagle-like legs for the forelegs AND having wings, I combined the two. Griffins now can either walk with their wings folded up like bats do when they're on the ground, or on their hind legs. But like the dragons, griffins now have only four limbs. And the feline-looking tail
I even came up with scientific order names for the kinds of animals they are, though not in Latin. Dragons are of the order Kreslatashix (a word in a dead Goblin language meaning "scaly warm-blood"), which look reptilian but have some mammalian traits like hair (though usually not MUCH hair), endothermic blood, they give live birth, and they have mammalian type ears. (Dragons have batlike ears, Goblin ears resemble scaly wolf ears.) And yes, they're similar to therapsids in this way, but being from another world, they aren't related to therapsids.
The order Grehshakakla (same dead Goblin language's word for "milk birds") are like birds with some mammalian features, the most prominent of which is they lactate the way echinoderms do (which is essentially to sweat milk, and the babies lap it up with their tongues). But they lay eggs. Obviously, with their partially-feline anatomy, griffins are in this order.
By the way, griffins are going to come in myriad sizes, depending on species. All the way from being as big as lions, to ones as small as domestic kittens, and everything in-between. Lots of variation in colors, body shape, beak shape, etc. Not just raptor griffins, either, but fruit-eating griffins, nut eaters, woodpecker griffins, and so on.
This was cross-posted from https://fayanora.dreamwidth.org/1411948.html
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