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Reference

Mode:

Sculpt Mode

Brush:

Sidebar ‣ Tool ‣ Brush Settings ‣ Advanced ‣ Brush Type

Similar to the Grab brush, but instead only moves the geometry along the surface (using the area plane). This is useful for grabbing surfaces with a very specific direction, or without making too impactful changes to the overall object shape.

Brush Settings

General

Merknad

More info at General brush settings and on Advanced brush settings.