  We analyze a recently proposed extension of the Standard Model based on the
SU(4) x SU(2)_L x U(1)_X gauge group, in which baryon number is interpreted as
the fourth color and dark matter emerges as a neutral partner of the ordinary
quarks under SU(4). We show that under well-motivated minimal flavor-violating
assumptions the particle spectrum contains a heavy dark matter candidate which
is dominantly the partner of the right-handed top quark. Assuming a standard
cosmology, the correct thermal relic density through freeze-out is obtained for
dark matter masses around 2 - 3 TeV. We examine the constraints and future
prospects for direct and indirect searches for dark matter. We also briefly
discuss the LHC phenomenology, which is rich in top quark signatures, and
investigate the prospects for discovery at a 100 TeV hadron collider.
