And I have completed the second of the three great quests: I have destroyed the Empire Portal, which, had I not been so intrepid, eventually would have teleported thousands of Empire troops down to Avernum to crush all my friends and neighbors.
It turned out that the next two gates were just puzzles. One had a couple of doomguards, but those are much easier in this game than in previous ones. It was just a matter of finding switches to throw. The third gate was more of a puzzler. If you did it wrong you got to fight endless enemies. But, notice that there is a clear path from the front of a trapped room to the back, and you can completely avoid that fight. I fought a few but then reverted to a saved game and got through easily.
Even the actual fight at the portal itself wasn't all that bad. The enemies come in clumps and they're really not that tough until you get to the control room on the second floor. Just systematically take 'em all down, collecting loot along the way, of course, and then you're faced with another puzzle. But it's fairly easy to just bulldog your way through that one. I kept wondering where the Onyx Scepter was going to come in, but follow all the clues and smash what you can smash, and it eventually becomes fairly obvious what to do.
The Empire Portal Explodes!
Now then. I've still got massive numbers of wisdom crystals, and probably have enough herbs to make more. So the next trip will be to Patrick's Tower, where the gardner can craft the things. Then I will gulp 'em all down and see if I can get my spellcasters up to Adrenaline Rush in the battle skills: that gives you three rounds of action per turn. It's really difficult to get to that with the spellcasters however. I think next time I'll forgo trying to do that and just choose the Swordmage trait for my cleric and try to get 'em both up to full strength in Priest and Mage skills. (I have found it useful to give one point of Priest skill to everybody, including my two fighters. Sometimes it's helpful for them to cast minor heal.) Really I think getting both spellcasters up to full wizard/priest status would be more useful than Adrenaline Rush.
After that I've got to visit every trainer in the game to be sure I've used up all the possible skills.
And then, it will be time to chase down Garzhad, the game's final quest.
Sigh.