Dark Avenger CM 2 30% atk bonus bugged

[darkb1ader]

The CM 2 30% atk bonus of Dark Avenger sometimes goes missing when in dungeon or nest.
Kindly look into this please.

Thank you in advance.

[darkb1ader]

Left pic: town stat CM 2 30% atk bonus applied
Right pic: bugged stat CM 2 30% atk bonus not applied. Occurred usually after being debuffed by bosses before battling.

[Mender16]

I am also experiencing this bug right now. At first I thought there might be something wrong with my skill build, but after reading the patch note, I can confirm that there's a bug in DA's skill "Class Mastery II". Hoping that they could fix it immediately because it hugely affects the character and its game-play.