Note on "condition stoppers": Because of my party's make-up and the Pacifist Cleric's tendency to not miss (I never seem to get to see his dice rolls), I had to give most of my Solos a save at the beginning of the turn, in addition to the end, or they'd never get to do anything at all. In some cases I allowed that save to work on conditions that a save couldn't end.
Unfortunately, in the case of Acererak, the melee characters managed to just rush in and wail on him, pretty much before he could do much. Very anti-climactic.