Glenn Drover's Empires: The Age of Discovery - Plague Promo is a set of 3 new Capital Buildings that can be added to the tile mix, giving greater variety from game to game. There is one plague Capital Building for each of the three ages.
Age 1 Plague Building - Player succeeds on all discoveries in Age 1.
Age 2 Plague Building - Any colony with 3 or more population of any single color is reduced by one colonist.
Age 3 Plague Building - Player chooses one opponent colony and reduces it by 3 colonists.
The buildings are also compatible with the older "Age of Empires III" version of the game.
This document includes all the rules that are either missing or ambiguous in the documentation for AOE III, the Builder expansion and the Plague Promo.
Please go to http://boardgamegeek.com/filepage/82534/aoe-iii-rules-addendum for the updated version.