Layers > Sculpt using layers >
Merge two or more sculpt layers
NoteYou can only merge layers at the same subdivision level.

1. In the Layers window, hide any sculpt layers you don’t want merged. For more information, see Hide or show a sculpt layer.

   Any remaining visible layers on the same subdivison level will be merged.

2. In the Layers window, select the Layers window menu ( ), and select Merge Visible.