Inverse Lock Bone is an animation tool designed to fix foot sliding issues commonly found in motion capture data and manual keyframing. It works by locking a specified target bone, such as a toe or foot, and automatically recalculating the transform data of the rig's master or root bone to maintain that locked position.

The tool offers four lock types—Head, Tail, Center, and Entire bone. The first three adjust the location of the master bone, while the Entire option also recalculates the rotation of the locked bone. It integrates into Pose Mode under the bone properties panel and outputs individual keyframes for the recalculated transformations, which can be further smoothed or decimated in the Graph Editor.