Hey Team - It appears you implemented a well-intended and justified fix to the mob tagging issue: A leveling player tagging mobs that players not grouped with the leveler then finish off. The leveler gets the XP. Something like this caused drama during the first WOTLK go around.
In testing today I can see the effects of this fix, if a player outside of the tag group does damage to that mob, it appears to pull xp away from the tagging player, seemingly in proportion to the dmg done by the non-tagger(s). This is all good and makes sense; however, an unintended consequence seems to be that damage done to mobs by non-players is also now degrading the xp for the tagging player. For example, in UK Proto-Drake Handlers are casting Unholy Rage on Enslaved Proto-Drakes, which inflicts damage on the Drakes, degrading the xp earned by how much damage the debuff does. I’m guessing this wasn’t intended. If so, appreciate a fix!