  We propose a novel dark matter (DM) detection strategy for the models with
non-minimal dark sector. The main ingredients in the underlying DM scenario are
a boosted DM particle and a heavier dark sector state. The relativistic DM
impinged on target material scatters off inelastically to the heavier state
which subsequently decays into DM along with lighter states including visible
(Standard Model) particles. The expected signal event, therefore, accompanies a
visible signature by the secondary cascade process associated with a recoiling
of the target particle, differing from the typical neutrino signal not
involving the secondary signature. We then discuss various kinematic features
followed by DM detection prospects at large volume neutrino detectors with a
model framework where a dark gauge boson is the mediator between the Standard
Model particles and DM.
