After seeing how the abilities of runic mace and wristbands weren’t correctly counting in-battle mastery, I wanted to check the brimstone effect of Warlock’s imp gems. Each brimstone stack is supposed to increase dark and fire mastery by +2%. However, as it happened with runic mace and wristbands it is counting the mastery before the battle instead the actual in-battle mastery.
To show this, I started a battle with a 5,234 dark mastery build and 4 dark spells (70% increase in dark mastery). Therefore, I started the battle with 5,234 + 5,234 x 0.7 = 5,234 + 3,664 = 8898 dark mastery.
After exploding 1 imp gem, I should be getting a 2% boost to my current fire and dark mastery. That would mean 387 x 1.02 = 395 red mastery and 8898 x 1.02 = 9,076 dark mastery. However, I got this:
A quick calculation told me that the 2% is being applied to the mastery I had before the battle started: 5,234 + 5,234 x 0.7 + 5,234 x 0.02 = 5,234 + 5,234 x 0.7 = 5,234 + 3,664 + 105 = 9003
As I said before, this seems to be exactly the same issue as with runic mace and wristbands.
Thank you for your time and hard work.