I was politely asked by an old friend if I would convert our favorite solo dungeon (Maze of the Riddling Minotaur) to PF2E. Since we both have been playing this one module for, like, ever, and I have converted it to multiple systems over the years, I agreed. A majority of the monsters exist in the Bestiary (just got it last night, Yay!) and I can adjust existing ones with the Elite add-on, I find it difficult to create the necessary Obsidian Golem that weighs in around a CR of 6 to 8. I don't think adding the Weak adjustment will work on an existing monster.
Obsidian being volcanic glass would be weak possibly to sonic and bashing?
Explosive death possibly with glass shards flying about? (ala the skeleton trait)
Based on a Minotaur shape so Large size.
Can't think of any reasonable antimagic tho...
On a side note, adjusting the size of a monster from Medium to Large like an Animated Statue, bump up CR by 1 and give it Elite mods? Or does making something Large from Medium give different modifications? Would adding extra abilities to an existing creature bump it by a +1 CR, say a ranged attack of a burst of flame (1d6 per 2 levels)?
I humbly request input from the various and sundry Creature Forge Experts in residence. Thank you.