As noted in many places over the last years, it could be a nice idea to implement some kind of ambush mechanic. So this is my attempt.
As a concept this patch gives the Gauls an "ambush camp", which can be build anywhere and is not directly/ automatically targeted by the enemy.
infantry units can garrison inside it and ambush the enemy.
Credits go to @wowgetoffyourcellphone from whom I got the "grove" idea, after which the camp is modeled
and @bb who gave some helpful tips
Here is a short video demonstrating the core mechanic:
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