What happened to Jamie Maddox's other duplicate?

Question

We only see one of Multiple Man's duplicates, the one who goes into the 'Bishop' future.

When this duplicate

is killed by Layla

Jamie wakes up. Does that mean the other duplicate is already dead?

Answer 1

The other dupe is not already dead (or arguably maybe he is, since he refers to himself as such), but at some point becomes the villain Cortex, who targets depowered mutants.

According to Forge after M-Day, all potential futures with mutantkind flatlined. However, when the the mutant since M-Day was born two new futures popped up. To explore these new futures, Cyclops and Emma Frost recruited the help of Madrox the Multiple Man. Madrox and Layla Miller traveled to Eagle Plaza in Dallas, Texas to meet with Forge. Madrox create two dupes to send into the two remaining mutant futures who would recover all the information they could and then die so their memories would transfer to Madrox. Cortex was one of these two dupes.

Once this dupe had gained the information about this mutant future he attempted to return home. By unknown means he became trapped in a vortex where time did not exist.[4] It was here that he was captured by Tryp and Anthony Falcone. Tryp and Falcone then made massive alterations to him and added cybernetic modification to turn him into a doomlock, a being that could alter time without creating divergent timelines. He had become Cortex.

Cortex was then sent back in time with instructions to kill specific key individuals who progeny would become leaders of the Summers Rebellion. To accomplish this, Cortex could mentally control several people at once.

Despite being a duplicate of Multiple Man, Cortex can no longer create duplicates on his own or be absorbed Madrox Prime. It is unclear if this is because of his prolonged separation of Madrox or because of the process that turned him into a cyborg.

He has seemingly only appeared in 9 issues, the last of which, X-Factor (Vol 3) #50, is the one that revealed his origin.