I absolutely love the swamp and marsh fills. You can see the water! Most of the overland swamp and marsh fills don't include that, though you can draw your own rivers lines on top.

Very nice.

Ralf shows another approach in this Height Transitions video as well

Good eye! I will fix.

Thank you!

Congratulations, Wyvern -- and indeed, very apt to come when you're designing a map in Jim's memory. I've been pondering ideas for something to do in his memory, too. Maybe a temple or shrine dedicated to "Saint Jimpey, patron saint of navigators."

I love how that central corridor is made to look snake-like, culminating in a room that looks like a serpent's head. But I especially like the two wall extrusions near the "head" also look serpentine.

Can you explain how the top structure relates to the bottom (or is it a secret?). There doesn't appear to be any entrances to that part. Are they secret? Is it accessed magically? Is it on the same level, north of the larger structure, or another level higher or lower?

I'm very intrigued by this.