Hi Curfew, A lattice is Symetrical,(whatever is done to one side reacts on the other) But a terrain is not. Be sure to make the terrain solid by selecting "Solid" from the drop menu in the terrain editor, if you want to do boolean operations with it. in case you may not know The clipping bracket is located on the right side of the canvas in the terrain editor. click and drag on it . also Alt/click on the bracket to re-set it . good luck Hope this helps Hawkfyr

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