apqurhf: hello. i haven't played "arcanum" for like 15 years, and started now again with the gog version. in the mines of the black mountain clan i am confronted with a huge problem, which wasn't there when i played the game years ago: golems in the black mountain clan mines are level 25 and additionally have desintegration spell.
The golems in the mines were always level 25, and have access to the Stone Throw spell
Disintegration isn't even an Earth spell; it's the final spell in the Force college. If they genuinely are using that spell, your only viable option is to reload the game from scratch and start over. It's safe (and recommended) to install the UAP, but stay away from any other mods for now
If (as I suspect) they're actually using Stone Throw, then it's just a matter of your party not being ready for that dungeon — which is famous (infamous?) for its abrupt spike in difficulty, compared to the main quest leading up to it. Like BurningSheep, I recommend doing side quests, and exploring Tarant's sewer system and/or Ashbury's castle, to build yourself up some more before tackling it
Also, be sure you're playing the game in turn-based mode rather than real-time; the real-time mode was added late in the development process, and is known to be imbalanced to the point of almost totally broken