Lex Luthor's offer to Martian Manhunter is very simple. Come to this area in the desert where we they can talk. He's told not to mention a word to Hawkgirl as him and Lex Luthor are psychically linked. Hawkgirl says that she trusts him no matter what. Martian Manhunter disables Hawkgirl's mind.
He arrives in the base where Lex Luthor goes over his plans with Martian Manhunter. He wants them to merge into the perfect Martian Human hybrid and become the perfect Apex Predator. They can become the being that Perpetua created to help her rule the multiverse.
But Martian Manhunter refuses. He doesn't want to contribute to the creation of a being that could end up ruling the multiverse. Lex Luthor planned for this. Unfortunately, their psychic link aloud Lex Luthor to hack Martian Manhunter's body and merge with him forcefully.
Hawkgirl threatens with everything within her that she will smash Lex Luthor into a pulp.
The issue ends with the Justice League looking for the anti-monitor and they instead find writing that predates the multiverse. It reads DON'T FOLLOW ME. Signed the anti-monitor.