  The exotic decay modes of non-Standard Model (SM) Higgses in models with
extended Higgs sectors have the potential to serve as powerful search channels
to explore the space of Two-Higgs Doublet Models (2HDMs) that cannot be studied
effectively using conventional decay channels. Once kinematically allowed,
heavy Higgses could decay into pairs of light non-SM Higgses, or a non-SM Higgs
and a SM gauge boson, with branching fractions that dominate those of the
conventional decay modes to SM particles. In this study, we focus on the
prospects of probing exotic decay channels at the LHC and a future 100 TeV
\emph{pp} collider in the context of Type-II 2HDMs. We study the three
prominent exotic decay channels, A -> HZ, A -> H^+ W and H^+ -> HW, and find
that a 100-TeV pp collider can probe the entire region of the Type-II 2HDM
parameter space that survives current theoretical and experimental constraints
with exotic decay branching fraction > 20%.
