A shock assembly for use with a motion tool deployable into a wellbore by a conveyance. The motion tool includes a mandrel operatively connectable to the conveyance or the motion tool, a housing operatively connectable to the motion tool or the conveyance (the housing having an opening to slidingly receive the mandrel and including a first and a second spring portion), a first spring slidably positionable in the first spring portion and having a first spring stiffness, and a second spring slidably positionable in the second spring portion having a second spring stiffness. The second spring stiffness being less than the first spring stiffness such that the first and second springs selectively engage as the housing slidingly moves about the mandrel in response to forces applied to the system to selectively restrict movement between the mandrel and the housing whereby the motion tool is vibrated.