At the end of Adventure Comics #6/#509 it was revealed that Lex had been cloning something new but I don't remember if it was ever revealed what/who it was that he cloned. Was it?

Judging from the green skin, he went for one of the few beings more powerful than Superman: The Martian Manhunter. And going off the slenderness of the hand, I'm guessing it'll end up being New 52 M'gann M'orzz.

Guess he figured that with Martian Shapeshifting DNA, it'd be more malleable and adaptable, allowing it to mix with human DNA easier than Kryptonian.

you misunderstand...this is from preFlashpoint

Ah, sorry. My bad. I don't know then. Still, there aren't a lot of green aliens Luthor has access to. Brainiac and J'onn are the only ones that come to mind. And if you failed to clone a Kryptonian, but wanted a superpowerful clone nonetheless, what better than a Martian? May not be M'gann, but I'd still say it's a Human/Martian Hybrid.

@jonsmith: see prior to this Luthor had been in jail and General Lane had been forcing him to study Brainiac so I'm kind of thinking that it involve Coluan dna