Yep yep yep on pretty much all that.
The only teachers he would have at the moment would be Maelen and Antefalken possbily Damien (but doubtful) and of course, the greatest instructor of all time. The Mighty Me Demon!
Oh an Boggy too. We shall teach him how to torture, mutilate and eat Astlanians. How to terrify small children, even more than we do now by default.
There is a plethora of information to be gleaned about secretly hiding under a child’s bed and terrorizing it. Oddly enough, not seeing the monster under the bed is often worse than seeing it. if you see something, you can try to grasp it/encompass it/understand it. Something can’t see, but only fear is there, is left completely up to one’s imagination, and imagination is often scarier than reality.
Smaller to medium, usually they just grow bigger, wartier, scarier. At the higher levels, they pretty much stick to their older form and add more of their own choosing (e.g. shape changing–Exador/Ramses/Bess/Lillith/Asmodeus each have quite a few forms they can assume)
Wow, you’ve got me nostalgic. I haven’t terrorized a child in a long time. I think I’ll journey to an Earth and hide under some beds and be really spooky tonight!