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The light is at the same position than the camera.
When the mesh rotates (the rotation is part of the animation of the mesh. This is just a rotation of the root bone), the back of the ninja should be lit but is not.
I like working with rank-outsiders, as long as they give themselves the means to achieve their ambitions.
I have changed the default state to animate normals. Since we also have lighting enabled by default this seems to make more sense, even if it's slower.