Superman #686 (2009)

YESTERDAY AND TOMORROW While Superman leaves the planet Earth to take care of business on New Krypton, he leaves Mon-El in charge of protecting Metropolis. Superman provides him with a signal watch to give to Jimmy Olsen should he ever need him. He also asks Guardian and John Henry Irons to look after him.   Mon-El is virtuous, but is not entirely familiar with the intricacies of super-heroing. He gets into a battle with Rampage and flies her a mile into the air, whereupon he drops her to the ground without any real knowledge as to whether she will survive the fall or not.   Guardian addresses Mon-El and decides to give him a secret identity -- Jonathan Kent. As Kent, Mon-El joins the Metropolis Science Police. Mon-El meets Billi Harper, the niece of the original Guardian, James Harper.