The hinted diphoton excess at a mass of 750 GeV suggests the existence
of heavy quarks that mediated the resonance production via gluon fusion.
The decay of the heavy quark into Sq, with q being a SM quark, could
provide a new search channel for heavy quarks.
We consider the case of a singlet vector-like partner of the top quark
and show that it can be searched for at the 13 TeV LHC through its decay
into a scalar resonance in the 2\gamma+\ell final state, especially if
the diphoton branching ratio of the scalar S is further enhanced by the
contribution of non coloured particles. We further show that
conventional heavy quark searches can be sensitive to this new decay
pattern also when S decays into jets by slightly tightening the current
selection cuts. Finally we comment about the possibility of
disentangling the heavy quark decay to St from other standard decay
patterns by scrutinising appropriate kinematic distributions.