Smooth Move Tool
The Smooth Move Tool works on Vertex and Position ducks only.
Select one or more layers, then select a bunch of ducks (use Control-A to select all the ducks at once). Draw one of the selected ducks and all the nearby ducks will move with it. What counts as a 'nearby duck'? That depends on the value of the 'radius' in the tool's options.
If all selected ducks are moving when you drag one duck, try reducing the 'radius' setting. I find that a value between 1 and 3 works well.
When dragging a duck, the nearby ducks move differing amounts, depending on how close they are to the duck you're dragging. This gives a localised 'scale' effect.