Flying At the beginning of your end step, you gain 3 life if Sphinx Sovereign is untapped. Otherwise, each opponent loses 3 life.
"What rises without legs, whispers without a voice, bites without teeth, and dies without having life?"
Official Rulings for Sphinx Sovereign
10/1/2008 : The ability checks whether Sphinx Sovereign is tapped or untapped at the time the ability resolves. If Sphinx Sovereign is no longer on the battlefield by then, the ability checks whether Sphinx Sovereign was tapped or untapped at the time it left the battlefield.