Where: Balinok Mountain - Lower Caverns - Abandoned Mines
When: <10 minutes before this post (@debug used)
What: Found a Large Black Pudding that had magic immunity (and strong at that) while there was none at all on every one I've killed so far (including one in that area just before it)
Specific spell resisted: Web, at least 15 times (it, grease, and many other spells had worked on every other one)
Also suspect it had see invisibility (it's movement pattern didn't seem to follow that of the AI following by sound)
Side note: Normal Black Puddings seem to be vulnerable to both acid and negative energy, while the flavor around them suggests they would not be, but they are immune/resistant to electric damage if memory serves (unsure about the magic immunity one)
not sure if this is intentional or not (can make a separate post for it if desired)