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  1. Home
  2. Abbasid Dynasty
  3. Technologies
  4. Preservation of Knowledge
Preservation of Knowledge

Research Technology

Preservation of Knowledge

Abbasid Dynasty

Abbasid Dynasty

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

Patch History

2025-12-04 Patch 15.2.7380

Abbasid Dynasty

  • Preservation of Knowledge upgrade no longer reduces Naval Arrowslit emplacement cost.

2023-05-16 Season Five Update

Preservation of Knowledge technology

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

Abbasid Dynasty

  • Fixed an issue where Outpost emplacements were affected.

2023-04-04 Patch 6.1.130

Abbasid Dynasty

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

2023-02-09 Season Four Update

Abbasid Dynasty

  • Preservation of Knowledge bonus reduced from 30% to 20%.

Research at

    Costs
    25wood
    75gold
    30time