ACP of Masterworked Mithral Agile Breastplate +2

[Athris of the Nine Dragons]

RAW I think it should be zero but Hero Lab says -1. What does the hive mind say?

[vhok]

I can see why your asking based on the title. It’s not really “masterwork” mithral because it can’t be non masterwork. The masterwork bonuses are included in mithral and calling it masterwork mithral is redundant, it cannot be non masterwork. Yes it is -1

[Belafon]

You can, however, add the comfort property to your armor (5000 gp). That would reduce the armor check penalty by one (to 0).

Or use the Nimble armor modification from Adventurer’s armory 2. This has some tradeoffs but includes reducing the ACP by one.

[Mysterious Stranger]

It depends on what you are doing. An agile breastplate reduces the ACP when making climb checks and for acrobatics checks made to jump by 1. So a mithral agile breastplate would have a -1 ACP for everything except climbing and acrobatics check for jumping. For climbing and acrobatics checks for jumping it would be 0.