This bug is for Shadow Priests only. Its also only useful if the Shadow Priest in question gets the Mark.
In Suarfang, when he cast the Heros Mark on a Shadow Priest, most priest know that using Dispersion will make the Hero's Mark do only 100-200 damage to them. But did you know that the mechanics of Dispersion also allows that Mark to be removed?
This exploit is useful if 2 or more players get the Mark and the Shadow Priest is the 3rd. It requires a Paladin as well as a druid to help with it to be useful.
How it works:
->Shadow Priest gets the debuff. Shadow Priest then uses Dispersion. While the shadow priest is in Dispersion, have a Paladin use Divine Intervention.
Heres the hard part. Dispersion is a small couple second buff. While in dispersion and you get DI'ed you must IMMEDIATLY remove it before you get out of Dispersion.
Dispersion buff will get locked onto the player, however its not there. Its a client side glitch that shows your character with the buff at 0s and will remain flashing, however when the DI'ed is removed, the hero mark will now only tick for 100-200 every time it ticks as if still under Dispersion.
The Paladin then gets Brezzed by the Druid.
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1. Shadow Priest gets mark
2. Shadow Priest dispersion
3. Paladin DI'es the Dispersioned Priest
4. Shadow Priest while DI'ed with Dispersion takes off DI before Dispersion wears off
5. Shadow Priest is now Dispersion Bugged.