Spring RTS Engine

That could be said of any terraforming, but I think the SY's will ahve gottn pathfinding working past the initial changes in the maps terrain.

If you do create such a wall at least tint the changes terrain in some metallic colour to show it isnt ordinary ground but constructed ground.

A very interesting idea AF.

Perhaps a unit that raised the ground between it and its nearest counterpart slowly over time to form a rising wall. Though to stop it you'd have to destroy/reclaim it, perhaps with ones turned permanently off to provide walls that get steeper and steeper for entrances.