I recently started a new England campaign - cue much nasty usage of sharpened stakes. Anyway, I was fighting against the French, and peculiar chaps that they are, they decided to push half a dozen trebuchets, catapults and ballistas over the bridge I was defending. Those that survived the hail of missiles then carried on pushing, and in the process, ran over and removed some of my stakes.
So, they have a counter - of sorts - perhaps something a carracio standard type unit could have a use for.
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