  We study dynamics of relativistic Coronal Mass Ejections (CMEs), from
launching by shearing of foot-points (either slowly - the ``Solar flare''
paradigm, or suddenly - the ``star quake" paradigm), to propagation in the
preceding magnetar wind. For slow shear, most of the energy injected into the
CME is first spent on the work done on breaking through the over-laying
magnetic field. At later stages, sufficiently powerful CMEs may experience
``detonation" and lead to opening of the magnetosphere beyond some
equipartition radius $r_{eq}$, where the energy of the CME becomes larger than
the decreasing external magnetospheric energy. Post-CME magnetosphere relaxes
via formation of a plasmoid-mediated current sheet, initially at $\sim r_{eq}$
and slowly reaching the light cylinder (this transient stage has much higher
spindown rate and may produce an ``anti-glitch''). Both the location of the
foot-point shear and the global magnetospheric configuration affect the
frequent-and-weak versus rare-and-powerful CME dichotomy - to produce powerful
flares the slow shear should be limited to field lines that close near the
star. After the creation of a topologically disconnected flux tube, the tube
quickly (at $\sim$ the light cylinder) comes into force-balance with the
preceding wind, and is passively advected/frozen in the wind afterward. For
fast shear (a local rotational glitch), the resulting large amplitude Alfven
waves lead to opening of the magnetosphere (which later recovers similarly to
the slow shear case). At distances much larger than the light cylinder, the
resulting shear Alfven waves propagate through the wind non-dissipatively.
Implications to Fast Radio Bursts are discussed.
