Shades of Darkness

I don't think so. At around the same time, Vittorio managed to win tests using a default Chaos Warlock-Black Dragon-Paladin build. But subsequent enemies are not vulnerable to Chaos at all, so it's better to think in advance about Darkness/Summoning on the Mentor before facing Jorgen. In my playthrough, Wisdom worked well – there is a guaranteed Tome of Power on the map, and with this combination, I was able to learn Implosion, Berserk, and Hive without the skill, which I used closer to the end.

Thank you for the advice, I will take it into account.

Thank you for all the advice, point by point.

But I didn't wait long enough (I was playing at the time, not monitoring the forum), I did it my own way, and I don't want to reveal everything in advance because it caused wild emotions)). I'll tell you everything when I'm done, not necessarily in the next few days, but I'm sure I'll be able to, and I won't have to replay what I've already done. The Faceless Ones (Dark Assassins, I think) are SOMETHING, I thought the Puppet Masters were the best, but I was so wrong...

Also, these devils, Frederick and Orin (I think), respawn every two days, right? And will they stop running around when I take all the castles, three from each?)