The kid is a paralyzed boy that Black Adam empowered with Captain Marvel style powers, and the crocodile has been his meek sidekick/comic relief for several issues, constantly complaining that he's hungry. The kid reverts back to his normal form by saying Black Adam's name, which the crocodile tricks him into doing so he can kill him, because the crocodile has been biding his time for such an opportunity. It ties into the Egyptian mythology that underlies Black Adam and his backstory.
It doesn't work too well isolated like that, but if you read all of 52 up to that point, it's a jawdropper.