How do terrain-based unit promotions work?
If I promote a unit so that it is better a fighting of rough terrain for example.
When I am in combat and attacking an enemy, who needs to be in the rough terrain them or me for me to receive the bonus?
Solution 1:
In general, it is determined by the tile on which the attacked unit is standing.
So, in case of melee units, it's where the combat takes place - i.e. in the hex containing the defending unit.
In case of ranged units, attack bonuses depend on the hex on which the target is standing.