  We study the decay modes of a new, light spin-0 particle, arguing that if the
mass of the (pseudo)scalar is ~11-15 GeV, it can have an appreciable branching
ratio into bottomonium, in particular the rare eta's. Using non-relativistic
QCD (NRQCD), we calculate its decay rate to bottomonia for mass splittings
greater than the typical momentum transfer within the bound state. It can
exceed that of decays to other Standard Model fermions under the assumption of
couplings proportional to those of the Standard Model. At smaller splittings,
where our computational methods break down, we estimate the rate into
bottomonia using data-driven methods. When the spin-0 state decays to
bottomonia whose mass is too light to produce B-meson pairs, we get a
qualitatively new experimental signature, decays to b-quarks invisible to
b-tagging. Such a light, spinless particle can arise in extended Higgs sectors,
making this channel potentially observable in decay chains initiated by the
subdominant decay of a Standard Model-like Higgs to a pair of them.
