The LHC may produce light, weakly-interacting particles that decay to dark matter, creating an intense and highly collimated beam of dark matter particles in the far-forward direction. We investigate the prospects for detecting this dark matter in two far-forward detectors proposed for a future Forward Physics Facility: FASER$ u$2, a 10-tonne emulsion detector, and FLArE, a 10- to 100-tonne LArTPC. We focus here on nuclear scattering, including elastic scattering, resonant pion production, and deep inelastic scattering, and devise cuts that efficiently remove the neutrino-induced background. In the invisibly-decaying dark photon scenario, DM-nuclear scattering probes new parameter space for dark matter masses 5 MeV $lesssim m_{chi} lesssim$ 500 MeV. When combined with the DM-electron scattering studied previously, FASER$ u$2 and FLArE will be able to discover dark matter in a large swath of the cosmologically-favored parameter space with MeV $lesssim m_{chi} lesssim $ GeV.
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