Building hills in Hals does indeed take time...
...but ripping hills from RWG or NAV, then placing them into your prefab, takes very little time at all.
Especially if you're fluent in the
I asked Hal to put in.
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In your case (And I'm making up numbers here), I would rip a hill range, cut the layers to the height of your enbankment, say 12, cut the depth, width, and call it a day.