To spare a life, Thor makes the ultimate sacrifice! With the fate of his friend Eric Masterson in the balance, Thor steps in - and finds himself once again bonded to a mortal form! But which deadly foe will bring about such dire straits? Could it be Quicksand? The maniacal Mongoose? A new Executioner? Or as an untethered Asgard drifts into the Negative Zone, Annihilus?