Oh, I'm quite confident that if Izaq is spent I've pretty much won. The giants can't compete in research nor gems, and without Pythium there's no one left to dispell the evil globals. Also, with my income (46 death gems a turn, +a lot of astral) the globals come right back up again, even if the unlikely happens. I'm happy to be proven wrong, of course, if you want!
In the Faerun game I made an observation that if Ermor gets big enough it should win based solely on momentum. It's dang tiring to try and take Ermor's castles since they are worth very little to everyone else, especially with low magic sites, and very hard to take; I'm sure Izaq noticed that my endless hordes could tear down the walls much quicker than any army he fielded. Specifically since even though mindless units defend castles at 1/8 efficiency, they will still contribute a great deal if there's a sufficient number available.
Also, with Ermor one can just play the odds: I'm sure I've lost battles at about a rate of 4:1 or something, but the few victories are much more relevant than the losses. No real tactics necessary: just lob the undead at the enemy and hope that he doesn't have too much defense available.
I'll comment some more with better time; what says the good doctor about continuing? If you guys want to test things out I'll be happy to provide the testbed
Re: nightmare
Threaded Mode