The searches for particle Dark Matter (DM) have mostly focused on masses below 100TeV owing to the unitarity bound on thermal DM. In this talk, I will point out some intriguing dynamics in a confining dark sector that opens a vast parameter space beyond the unitarity bound.  The key observation is the effect of the first order confinement phase transition in a broad class of confining models that dramatically suppresses the DM abundance. While the effect is independent of the type of portal between SM and the dark sector, I will also study a specific model and further interesting dynamics that it gives rise to in such sectors. This study motivates broadening the scope of current heavy dark matter searches to a new part of the parameter space.