Ok this is a little convoluted... I'm searching my library, and choose to play a Panglacial wurm. When playing it, I activate a Chromatic Sphere replacing the card draw with Forbidden Crypt, with no cards in my graveyard, I would lose, but Lich's Mirror replaces the loss.
I control but don't own another sphere, so I still have it in play after the mirror's effect.
Seeing as I am still searching my library, can I look at the new top card before deciding to activate the second sphere to pay for the wurm's cost?