My character is a Shaman. I purchased four ranks of the Enhanced Pestilence AA under the Class tab. According to the description provided in the AA window it should extend the length and damage of Damage Over Time spells with a duration of longer than 18 seconds by 6 seconds per AA rank for a total extension of 24 extra seconds (four ticks) at rank 4. This AA is broken. I am not getting any extra ticks of extension from this AA to the Damage Over Time spells I have cast and parsed out.
These AA lines don't extend dots anymore, instead they just increase the base damage of the dots, which is much better due to quick kills. https://www.raidloot.com/aa?name=enhanced pestilence&effect=&class=Shaman&tab=&exp=All Max Rank that link shows the actual effects This passive ability increases the base damage of your damage over time spells that have a minimum duration of 4 seconds by 42 seconds worth of damage.
