Another gravedig... but after trying some Ultima, I started thinking about Theldrow and decided to look at it again.
Theldrow is too difficult if you ask me, and I"m honestly not sure if anyone's ever finished it without cheating. It's just too easy to lose your character to corruption or getting stuck, and there's no reliable way to build up a character given how limited resources like money are.
Following BW's lead, I played through with Pandora's Box. I was able to find almost all the stats that influence you, which made me invulnerable. BW, you're right that there are multiple variables affecting clerical spells, one for each of the five levels, a general one for divine favor, and a measure of devotion to gauge experience. I also agree that experience tracking doesn't seem to work correctly. The only thing I could find was a spell usage counter that probably increments your magical ability, but it resets when you save/quit. The chance-to-cast calculation eluded me as well; it's some combination of values, possibly including ones I've missed.
Regarding your other comments, The Void and Improvement both apply minor changes to your stats, only The Void has a chance to fail and de-improve your character or kill you outright. And it seems only Berabaku's temple is in the game. I bet you're right that he planned to add more as he was continuing to add new features and spells up until the last release before he decided to focus on building Delver instead.
Anyways, my brief review:
Complaints about difficulty aside, I enjoyed Theldrow. It's strangely captivating. When trying the black and white version, it has a really nice atmosphere, even without music or sound effects. There's elements reminiscent of Cythera (picking locks, bashing doors, or using magic to proceed) but a completely different setting and plot.
It is very short. There's a lot of spells and options the player has, but in reality, you'll only end up using a few of them. The bugs and occasional crashes hinder an overall fun experience, especially around the ending when you're trying to open the portal. Once you do reach the end, it's far too abrupt. He definitely planned to expand it and release a sequel in some form, but while I would like more of this story, we got Cythera instead, so I don't mind!
Since so little Theldrow material is out there, I recorded my play through and posted a Let's Play Theldrow! (Cheater's Edition) video of the complete game.
Additionally, it seemed a shame not to share all my findings about relevant values and ways to cheat in Pandora's Box, so I made a small Theldrow - Tips & Cheats page on Cythera Guides.
Thanks to mrdav from Macintosh Garden, I was also able to upload a copy of Theldrow's mythology. It's an interesting read. There's really nothing in the game that suggests a shared universe with Cythera, but parts of this document do in my opinion. Lots of -ari's and -ali's, but it seems possible to me that Cythera could be yet another Outari within the Void. That matches with the Elemantali being part of the Outari (elemental beings in Cythera?), which would make the Outari something like the "barrier" and the Eldari the "chimera" in Cythera's lingo. Finally, I'd point out that Theldrow's god of the Void, Yeqy, was a mortal wizard who learned control over the Void through magic... maybe like the author of the Cipher Manuscript?
That discussion may be worth another topic in itself, but for now, I hope everyone likes the abundance of new Theldrow content to explore!