I was questing in Aether Wroughtlands and a quest that gives me a maedjinn illusion still shows while mounted. Is there any reason why all hunanoid illusions can't do this? like my goblin illusion, or orc, etc. I can understand lion/wolf/bear forms not showing, but why not all 2 legged forms?
Animation skeletons. Simply put: there's a lot of bipedal humanoid models that *DO NOT* use the same animation skeletons as the player races. The mounts were painstakingly tuned to allow the player races to ride on mounts in various methods, but the majority of monsters in this game don't have the animations to allow them to sit in a saddle or fly with wings from their backs or even crouch down to ride on something like a horse-drawn chariot.
It has to have a player skeleton in them. There's not enough time in the day to animate every npc so they can ride mounts.