I think he means how during the generation process the terrains are disabled while generation takes place, then re-enabled once the data is prepared. I assume he's reading in the marker nodes prior to engaging the generation process. You could remove the generated terrains from MapMagic's awareness so that it thinks it's generating new terrains, then when it turns new ones on, figure out the location, and destroy any old terrains. I think your approach is good @YolanOTHER . The way I do it is to specify the tower placement in code and/or leave it up to noise based placement, instead of reading markers, but then it's pretty much the same workflow. I don't reflatten during runtime though, I just generate the data prior to turning them on once.