  Nascent neutron stars with millisecond periods and magnetic fields in excess
of $10^{16}$ Gauss can drive highly energetic and asymmetric explosions known
as magnetar-powered supernovae. These exotic explosions are one theoretical
interpretation for supernovae Ic-BL which are sometimes associated with long
gamma-ray bursts. Twisted magnetic field lines extract the rotational energy of
the neutron star and release it as a disk wind or a jet with energies greater
than 10$^{52}$ erg over $\sim 20$ sec. What fractions of the energy of the
central engine go into the wind and the jet remain unclear. We have performed
two-dimensional hydrodynamical simulations of magnetar-powered supernovae (SNe)
driven by disk winds and jets with the CASTRO code to investigate the effect of
the central engine on nucleosynthetic yields, mixing, and light curves. We find
that these explosions synthesize less than 0.05 Msun of Ni and that this mass
is not very sensitive to central engine type. The morphology of the explosion
can provide a powerful diagnostic of the properties of the central engine. In
the absence of a circumstellar medium these events are not very luminous, with
peak bolometric magnitudes $M_b \sim -16.5 $ due to low Ni production.
