Preservation of Knowledge — Abbasid Dynasty – Explorer – AoE4 World

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Research Technology

Preservation of Knowledge

Abbasid Dynasty

Reduce the cost of all technology and Age advancements by -20%.

Available in the Feudal Age (II)

Researched at

House of Wisdom

Patch History

Season Five Update

Help text updated to reflect that bonus applies to advancing Ages as well.

Fixed an issue where Outpost emplacements were affected.

Preservation of Knowledge cost reduced from 50 wood 125 gold to 25 wood 75 gold

Costs

25

75

0:30

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