Wrathful Advance's SFX used to be present on all Heavy Attacks as long as the ability's crit buff is active, but at some point after Update 34 the SFX broke completely and was only present on a few melee classes and is only heard when the ability is targeted on enemies.
This fixed the issue with other melee classes lacking the SFX on-target, but the growl is still absent when said buff is active.
Maybe it's not that gamebreaking of a bug, but the sound was one of the things that made Kullervo enjoyable for me and it gives that sense of raw power behind every Heavy Attack.
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