Biology

Biology
Availability
Introduced in	Age of Empires IV
Civilization	All civilizations except French and Jeanne d'Arc
Age	Imperial Age
Research
Researched at	University Madrasa Blacksmith (Mongols) Istanbul Observatory Hisar Academy
Food	500
Gold	1,000
Research time	90 seconds
Effect
Cavalry hit points +25%

Biology is a technology in Age of Empires IV that can be researched at the University in the Imperial Age. It is available for every civilization except the French and Jeanne d'Arc, who instead have access to Royal Bloodlines. Once researched, the hit points of all cavalry units is increased by +25%.

Civilization bonuses

• Abbasid Dynasty: Research speeds are +15%/+20% faster while Golden Age tiers 2/3 are active. If Preservation of Knowledge has been researched, this technology costs -20%.
• Ayyubids: Research speeds are 25% faster while Golden Age tier 2 is active
• Byzantines:
  • Research speeds are 30% faster per water level at buildings within the influence of a Cistern with the Dialecticus ability active.
  • Improved Biology is granted for free to Mercenary Mangudai and Keshiks when advancing to the Imperial Age with the Foreign Engineering Company. It does not stack with the Byzantines' own Biology.
• Chinese and Zhu Xi's Legacy: The technology researches 150% faster when the University is supervised by an Imperial Official. For Zhu Xi's Legacy, this can be improved to 300% faster after researching Regional Inspection.
• Delhi Sultanate: The technology is free, but takes ~14.7x as long to research (1320 seconds instead of 90 seconds).
• Malians: Technologies take less time to research based on how much gold has been obtained through trade.
• Mongols: The technology is available in the Blacksmith. Can research the improved technology for another 1,000 stone to grant cavalry +10% additional hit points (+35% total).

Changelog

• Originally, the base research time for the Delhi Sultanate was 5x default (450 seconds). With update 8324, this was increased to 15x default (1350 seconds). With Season Two Update 17718, it takes 12x as long (1080 seconds). With update 12.0.1974, it was increased to 1320 seconds (14.7x)
• Originally, Improved Biology for the Mongols provided an additional +15% hit points, for a total of +35%. With the Season One Update, this was reduced to +10% additional hit points, for a total of +30%. After update 12.0.1974, the total increase is +40%. With patch 12.1.2454, the total increase after the base reduction is +35%.
• Originally, Biology cost 300 food, 700 gold and increased the hit points of cavalry by 20%. With update 12.0.1974, it costs 500 food, 1,000 gold and increased the hit points of cavalry by 30%. With patch 12.1.2454, the increase was reduced to +25%.

Campaign version

Because the campaigns do not get rebalanced with each update, Biology maintains the same stats in each campaign that it had upon the campaign's release. Therefore, in the original four campaigns:

• Biology costs 75 food, 600 gold (with the Mongol improved version correspondingly costing +675 stone) and takes 60 seconds to research.
• It increases cavalry hit points by only 20%

In the The Sultans Ascend campaign:

• Biology costs 300 food, 700 gold and increases cavalry hit points by only 20%.