High Ruler against Dream Demon in the March PF. HR successfully hexed DD, and while she was cursed and hexed, her permanent death mark still went through, though she did not gain her enrage. That's all.
This is a known limitation of Hex -- against fighters with timer-based SAs like Dream Demon, Hex only stops new timers from starting, and will not prevent the effects of timers that started before Hex was applied.
There is a known bug with Dream Demon though where she won't function as expected while affected by Curse, which you may also be seeing from time to time. It's something we plan to fix for our next update.
