The best monster artwork is an inspiration to GMs. When we look through the monster manuals and bestiaries, we instantly know which monstrosities we want to feast on our player’s corpses. And for me, the Worm that Walks from the Epic Level Handbook has always been inspiring. It’s a fresh take on the physical corruption of magical pursuits. One distinct from the lich. If the monster has origins outside of D&D, I don’t know them. All I know is that they haunt my dreams, and I want them to haunt the dreams of my players as well.
I’ve actually repeatedly found the D&D 3.0 Epic Level Handbook to be one of the best supplements ever produced for 3.X. It is one of the very few supplements which focuses less on player options, and more on helping GMs to run their games better. The generator of 100 quest hooks, for example, is very good! The monsters presented are top notch, even if many of them are more powerful iterations of lower level monsters.
I’m kinda surprised I made it 13 weeks without posting anything from Wayne Reynolds before. That dude is prolific, and influential. Pathfinder goblins are his bath sponge.
No, really, they are.