I created a sorcerer and started to solo the game.
The hardest part of the game was 3rd floor of Watcher's Keep, where you can not use magic in some areas.
One of those was the "Wild Surge" area, where a few quasits cast magic like crazy. I was trying to kill them, and all of a sudden, Kangaxx appeared as a result of a wild surge.
I instantly changed area before getting imprisoned. Than made my preparations and came back to kill him. And got my 2nd ring thus.
(As if I needed any more gear
(I didn't use any mods whatsoever. Just the original patches. So I guess this is coded in the game)