I'm in the process of taking a solo assassin as far as I can reasonably take him (on core difficulty) to see how far he can get before the game just outpaces him (i'm betting that sooner or later, it will)
For Improved Illych, the rune assassins are the biggest pain in the buttocks--I can use detect illusion to counter their potion-quaffing invisibility, but it seems to me that no matter what, I can't detect them right at the beginning when they're just sort of chilling in the halls and corridors. Basically, then, my assassin has had to either 1) soak up the backstab, hoping for a critical miss or 2) set traps to nab the guy if he doesn't have puppy companions.
Failing those two options, I had to resort to leading them into enclosed rooms and slamming the door on them. Because of the limited number of such rooms, there was pretty much no way that I could deal with Illych and get his acorns (very important because of the summoning).
Was this intentional?
If not, is there something I can do locally to fix it?
thanks,
-wally