As it currently stands, Great Leaders are good for two things: to create Armies, and to rush projects to completion (as they are the ONLY means for rushing a Great or Small Wonder). I would like to see a third use added: "Begin Silver Age". The Silver Age represents a Great Leader's ability to bring an era of great prosperity to a region.
Essentially, when a Great Leader enacts a Silver Age in a city, that city (and ONLY that city) gains benefits equivalent to what it would gain during your Civ's Golden Age--an extra unit of Commerce and Production in any worked square already producing same for a duration of 20 turns. Each city can have only ONE Silver Age, and if a Silver Age overlaps your Civ's Golden Age, then during the turns of the overlap the city will gain the benefits of BOTH (+2 Commerce and +2 Production).
Essentially, when a Great Leader enacts a Silver Age in a city, that city (and ONLY that city) gains benefits equivalent to what it would gain during your Civ's Golden Age--an extra unit of Commerce and Production in any worked square already producing same for a duration of 20 turns. Each city can have only ONE Silver Age, and if a Silver Age overlaps your Civ's Golden Age, then during the turns of the overlap the city will gain the benefits of BOTH (+2 Commerce and +2 Production).
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