Age of Empires II: Definitive Edition · Cavalry technology
Bloodlines
Bloodlines adds 20 hit points to mounted units.
How it works
Bloodlines is listed as a Stable technology. It costs 150 food and 100 gold and takes 50 seconds to research. Its stated effect is +20 hit points for mounted units. The passage does not enumerate which units count as mounted or state an Age requirement or civilization availability.
Read the supporting references
Check the edition and source version for patch-specific details. Guide methodology.