I've been hit with a problem, where the last but one fight in RoA 3, where my party fights my doubles, includes an additional invincible character with buggy name and when I bypass this fight by splitting the party and sacrificing one character the game won't load the queen's chamber so I'm stuck right before the final fight. I watched some youtoube videos of roa3 playthroughs and it clearly is different from what I'm experiencing.

After some googling I was able to find that someone else was hit by the same problem 5 years ago but there was no solution. I'm using setup_realms_of_arkania3_2.0.0.27.exe installer. Was anyone able to finish this version of the game?
thanks

As I recall, you can bypass the double fight altogether by using magic (provided you have the right spells).

Try casting Visibili and/or Darkness before advancing.

that doesn't work anymore in this patched version. I tried the visibili, darkness, traversalis, extinguish light trick, nothing works anymore. also I can bypass the fight by sacraficing one character so the others can get through but after I get the message telling me that I'm about to enter the queen's chambers the level doesn't load and I just keep getting the message again and again.

at least we have youtube so I know how the game ends:-)

Hi,
I have had exactly the same problem (on CD with Czech localization). You should try some "non-damage" (like Domination Spells) magic for this enemy. You can see here https://www.youtube.com/watch?v=JlJ3ze5z550 how I have solved it (I killed nobody during the battle :))
Some magic spells I used:
-Evil Eye ("Zlý pohled/Ďáblovo oko") - Forces an opponent in combat to attack his own companions.
-Ball and Chain("Pouta a okovy/Koule a řetěz") - Keeps the victim from running away.
-Horriphobus("Horriphobus") - Instills a great fear in the opponent such that she might panic and run away in combat.

If all enemies are under any of these"curse", the battle ends. Maybe you can try some other "domination" spells, cheers!