I'm not even sure he's standing on a solid tile TBH, and wheytwut wouldn't work because of what darvin said. And coding the IMAWAL functionality would break stuff in other places, and couding it for that dungeon would be both a hassle and leave people wondering why it doesn't work in other places. And yeah, it gives quite a lot of regen and is in fact bloody powerfull with LEMISI and especially B2P. And since the dude's a pushover it would be a really easy-to-find Sensation Stone (still, 150 CP in most cases isn't too much, compared to certain other subdungeons).
While we're at it, we never had that subdungeon discussion we were meaning to have and the devs never got proper feedback. There's some real cluncky crap in there, and the way too good ones I can live with as a way of letting newbies hit the jackpot every so often. But the clunky ones get really old after a while.
To make clear - I'm not whining about ones like this one - I'll take my big blob of exploration and burn vicious to the ground with a bloodmage, don't get me wrong.
So the ones I'd do something about in a heartbeat if I were somehow an all powerful game developer:
Vegetarian Vampire: I like the concept. Really, I do. BUT! It's impossible to have the message and the "field" visible at the same time and clicking between them is tiresome since they're represented visually on the screen and with letters on the paper, and I have to keep mousing over them and... it takes me longer to figure it out every time than play half the map. Also, I can ussually only ever put togather 2 bonuses for all my trouble due to the uneven number of plants spawned and funky recipies, and individual rewards are a bit on the "meh" side. So it manages to both suck and blow - highest level of fiddling in the game required to get anything, impossibly low reward. After a while I just decide to skip it and keep concentration on the run (and you can tell how bad it is then, since you can't possibly lose anything while trying it).
That is all. That I can think of right now. If someone woke me up in the middle of the night with a flashlight into my face and a dog snarling at me and said "Vegetarin Vampire Subdungeon!" I'd go "NOOOOOOOOO! It's horrible! Gooood Coooonceeeept Thoooo!"