Cluster deformers let you control a set of an object’s points (CVs, vertices, or lattice points) with varying amounts of influence.

A cluster deformer creates a set whose members consist of selected points (CVs, vertices, or lattice points). You can assign a percentage weight to each point, indicating how much you want each point to be affected by any translation, rotation, or scale of the cluster set. When you transform the cluster, the points are transformed according to the percentages you specify.