Well, this is how I understand the card should work from its description
You choose the sacrifice at the beginning of the turn, but the combat zone wipe itself is not mentioned as initiated at the start of the turn, in which case it should be treated for what it looks like- a triggered card effect. According to the rulebook triggered effects take place during the time when pre-emptive effects take place, that is before character actions and ability cards resolve.
So, if I'm right, according to the description, the only thing that should be able to save you is moving your characters or pre-emptive abilities (the latter though would work only if played during your initiative).Here
is a link to the turn order for convenience.
I'll test it next time I play as I want to make sure that it indeed resolves during ability/action step and not during the triggered/pre-emptive step.