Transformed Villain?

[Firestorm23]

Ok im complety stumped on who it is, my money is on our luther....what are you toughts?....

[Firestorm23]

...........any one?

[PatrickG]

Could be Chemo.

Could be Superboy-Prime.

[Chip Whitley]

For those wondering, from the IC#5 solicit.
The DCU shakes apart as Superman of Earth 2 finally confronts our Superman. Meanwhile, heroes are disappearing throughout the DC Universe, a transformed villain returns, and the mystics of every world and dimension seek help from the very Spirit that is destroying them.
My guesses are:

Superboy Prime comes back from the Speed Force.

Anti-Monitor returns through either Alex Luthor or E-2 Lois.