  Non-axisymmetric features are found in the core collapse of a rapidly
rotating massive star, which might have important implications for magnetic
field amplification and production of a bipolar outflow that can explode the
star, as well as for r-process nucleosynthesis and natal kicks. The collapse of
an evolved rapidly rotating massive star is followed in three-dimensional
hydrodynamic simulations using the FLASH code with neutrino leakage. A rotating
proto-neutron star (PNS) forms with a non-zero linear velocity. This can
contribute to the natal kick of the remnant compact object. The PNS is
surrounded by a turbulent medium, where high shearing is likely to amplify
magnetic fields, which in turn can drive a bipolar outflow. Neutron-rich
material in the PNS vicinity might induce strong r-process nucleosynthesis. The
rapidly rotating PNS possesses a rotational energy of E>10foe. Magnetar
formation proceeding in a similar fashion will be able to deposit a portion of
this energy later on in the supernova ejecta through a spin down mechanism.
These processes can be important for rare supernovae generated by rapidly
rotating progenitors, even though a complete explosion is not simulated in the
present study.
