xienwolf
Deity
Destroy cities which follow AV, and destroy units with the Prophecy Mark promotion.
EDIT: Also destroying Hyborem too. And wiping out a civ which caused much AC to be created. Wiping them out generates some under your name, but removes all of it which is under their name. So for instance if Mahala razes the Order Holy City and 12 other cities, when you finally finish him off you will probably bring the counter down some. It would help if all of his cities were AV when it happened.
Oddly enough, I think that the AC goes up when AV spreads to a city, but by a set amount. It is supposed to go down based on how much population is in the city when you raze it, so you could actually lower the AC by spreading AV into a city before you wipe it out (though doing so would be tricky) if the city is large enough.
EDIT: Also destroying Hyborem too. And wiping out a civ which caused much AC to be created. Wiping them out generates some under your name, but removes all of it which is under their name. So for instance if Mahala razes the Order Holy City and 12 other cities, when you finally finish him off you will probably bring the counter down some. It would help if all of his cities were AV when it happened.
Oddly enough, I think that the AC goes up when AV spreads to a city, but by a set amount. It is supposed to go down based on how much population is in the city when you raze it, so you could actually lower the AC by spreading AV into a city before you wipe it out (though doing so would be tricky) if the city is large enough.