  Confining dark sectors with pseudo-conformal dynamics produce SUEP, or Soft
Unclustered Energy Patterns, at colliders: isotropic dark hadrons with soft and
democratic energies. We target the experimental nightmare scenario, SUEPs in
exotic Higgs decays, where all dark hadrons decay promptly to SM hadrons.
First, we identify three promising observables, the charged particle
multiplicity, the event ring isotropy, and the matrix of geometric distances
between charged tracks. Their patterns can be exploited through a cut-and-count
search, supervised machine learning, or an unsupervised autoencoder. We find
that the HL-LHC will probe exotic Higgs branching ratios at the per-cent level,
even without a detailed knowledge of the signal features. Our techniques can be
applied to other SUEP searches, especially the unsupervised strategy, which is
independent of overly specific model assumptions and the corresponding
precision simulations.
