Short Summary: At the beginning of the part two, Metamorpho is about to kill Green Lantern when the Justice League comes in and saves the day. Metamorpho is able to hold his own though, synthesizing kryptonite, and disabling Hawkgirl?s wings. His mastery of fire is also helpful against J?onn. Stagg videotapes the fight, planning to use the footage to help him sell his Metamorpho mutagen.
Rex escapes and tries to find Sapphire. He discovers that it was Stagg and not Green Lantern who betrayed him so he goes back to confront Stagg. Stagg is prepared for him though and freezes Rex. Metamorpho escapes once again though, and this time confronts Stagg while he is in the process of moving a new mutagen. During the battle, part of Stagg?s brain is transferred to the new mutagen and it becomes a huge slime creature.
It?s up to the Justice League and Metamorpho to stop Stagg before he gets to Sapphire. The Justice League is relatively ineffective, but Batman discovers a neutralizing agent. Metamorpho gets the formula and turns into the agent, destroying Stagg once and for all. Rex appears to have died in the process, but he manages to piece himself together to both the Justice League and Sapphire?s delight.