I can't get pass the Underdark level. I'm so low on hitpoints I cant get pass the big final battle with mindflayers. I've used up all my heal spells. Is there a place to rest? I don't see how I can get pass this final battle.

It's been a long time since I've played WotR, but have you brewed up the special potion to throw into the final room (and run back out again) that kills about half the Mind Flayers and sends some out into the previous room to fight you (in a weakened state)?

Characters with 20+ con should regenerate a hitpoint every few minutes outside combat. Psionic points also regenerate slowly over time, a psionic with the cell adjustment spell can heal hitpoints.

So you can try running the game in the background until your characters are healed, it might be faster if you increase the emulator speed with CTRL-F12.

What I did, is that I use the pot with healing water from the fountain of champions, back in the jungle with the halflings and yuan ti.

I just drop it and use it and it works as a portable fire circle.

(I don't know if it is unlimited though).

I was concerned about this too, but realized I had two El's Drinker at this moment.