Copy Rotation Constraint

The Copy Rotation constraint forces its owner to match the rotation of its target.

Options

Target
Data ID used to select the constraints target, and is not functional (red state) when it has none.
Order
Allows specifying which Euler order to use during the copy operation. Defaults to the order of the owner.
X, Y, Z

These buttons control which axes are constrained.

Invert
The Invert buttons invert their respective rotation values.
Mix

Specifies how the new rotation is combined with the existing rotation.

Replace
The new axis values replace existing values.
Add
The new axis values are added to the existing values.
Before Original
The new rotation is added before the existing rotation, as if it was applied to a parent of the constraint owner.
After Original
The new rotation is added after the existing rotation, as if it was applied to a child of the constraint owner.
Offset (Legacy)
This replicates the behavior of the original Offset checkbox. It was intended to be similar to the Before Original behavior, but does not work correctly with multiple axis rotations, and is thus deprecated.
Space
Standard conversion between spaces.