The Trials of Shazam #1 (2006)

The boy & the Man
After the first year of the New Age of Magic, Captain Marvel has taken up residence in the Rock of Eternity as the guardian of magic. He has more control over his powers than ever before. But after stopping the blood sacrifice of a dozen children to summon a demon, when he says his magic word to return to being Billy Batson, a devestating lightning strike hits him. He doesn't change into Billy Batson, but is in fact transformed again... but into what or who?
Release Date: 2006