The situation works as follows:
Item with +1 ( Armor Bonus ); Robe; Dex 16
[INDENT]AC = 14
[/INDENT]Cast Mage Armor, Robes become +4 ( Armor Bonus )
[INDENT]AC = 16 ??
[/INDENT]Remove Item with +1 ( Armor Bonus )
[INDENT]AC = 17.
[/INDENT]
For the record, my Monk with +1 AC Robes never had this issue with Mage Armor on.
That's because your Monk Robes were the thing that got enchanted BY Mage Armor.
This isn't clear, and I've never had this issue. Are you saying the robes are +1 AC or that you are equipping a ring, amulet or other Item with +1 AC?
It's a bracer that gives +1 armour AC, this problem is known but as far as I know it's unsolvable.
No matter how high the AC on your robe is your bracer's AC is always taken, even if it's the lower of the two.
Yup bracer +1 with Armor Bonus to AC is the thing mentioned here. Rings/belt/helm/cloak are deflection bonus, amulets are natural, boots are dodge. Different sources stack.
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That's not entirely true SFP, if you look at the math above, I gained AC from mage armor. It wasn't completely ignored. It looks like the script that reads mage armor and adds the benefits, reads for other armor bonus's and removes that value from the mage armor's granted ac (so they wont stack), but it looks like it's doing it twice for whatever reason. Edit: Or doing it once, and they don't stack to begin with.
Im wondering if it has something to do with the original Mage Armor script (when it stacked with armor), or with a different bug that was fixed elsewhere concerning the stacking or lackthereof.
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Anyway this doesnt effect me IG, I just wanted to give the bug to the Dms so they can do something about it if they wished.