The present article provides a short look at the strength of magnesium when twinning dominates the yielding behavior. The twin is approximated by a super dislocation to draw some tentative conclusions regarding the stresses required to: (1) thicken a twin to the aspect ratio observed experimentally, (2) propagate a twin over a grain, (3) thicken a twin within a stress concentration and (4) bow the propagating twinning front between particles. In all cases, relaxation of the twin stress field is important.