I was sooooo certain we would get here today! And then there were just endless random encounters instead. So here's a revised version:

fossegrim-lair-rev2.jpg

fossegrim-lair-with-grid-rev2.jpg

I've left the vegetation pretty much the same -- it's fairly shallow, and the terrain is flat enough that the plants should be able to grow right up to the edge of the water.

I did add some shadows and highlights to the underwater sections to give them some more depth.