  Magnon cat state represents a macroscopic quantum superposition of collective
magnetic excitations of large number spins that not only provides fundamental
tests of macroscopic quantum effects but also finds applications in quantum
metrology and quantum computation. In particular, remote generation and
manipulation of Schr\"{o}dinger cat states are particularly interesting for the
development of long-distance and large-scale quantum information processing.
Here, we propose an approach to remotely prepare magnon even/odd cat states by
performing local non-Gaussian operations on the optical mode that is entangled
with magnon mode through pulsed optomagnonic interaction. By evaluating key
properties of the resulting cat states, we show that for experimentally
feasible parameters they are generated with both high fidelity and
nonclassicality, and with a size large enough to be useful for quantum
technologies. Furthermore, the effects of experimental imperfections such as
the error of projective measurements and dark count when performing
single-photon operations have been discussed, where the lifetime of the created
magnon cat states is expected to be $t\sim1\,\mu$s.
