↑The Saracen team bonus displays +2 in the technology tree, even though it gives +3 attack against the standard building armor class. This is by design, since the description is meant to tell players about the effect in practice, not the value in the data files. Archers typically do a minimum damage of 1 against buildings. The +3 attack bonus against buildings results in an additional 2 damage being dealt to buildings; hence the +2 in the technology tree. However, in some cases the extra damage is indeed +3, such as against buildings with low pierce armor (Outposts, palisades, and Gates). For example, a Feudal Age Saracen Archer (4 pierce damage) attacking an Outpost (0 pierce armor) deals 7 damage instead of 4. The Saracen team bonus affects Skirmishers and Slingers because they are in the same unit class as the Archer-line. It does not affect Hand Cannoneers, because they have their own unit class.
Mameluke: Camel cavalry with ranged melee attack, and an attack bonus against mounted units.
Bimaristan: Monks automatically heal multiple nearby units.
Counterweights: Trebuchets and Mangonel-line +15% attack.*
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