Honestly, I don't know if this has been suggested. Please just tell me if so.
A purchasable item that takes up 1x1 space. It slows troops that attempt to cross it, leaving extra time for defences to attack. I think that it should be avoidable by jump spells, Hog Riders and flying units (duh). When connected to other ditches/mud patches, it will slow them over a further distance. As it upgrades, troops crossing it to slow further.


It could work though.


