- This character's history and characteristics are identical to that of her alternate dimension counterpart up until just before the Dark War, where the timeline split and the following changes took place.
Not long after their escape, Idris fell to Sebastian and his army. Two months later, the shelter in New York was destroyed and the Blackthorns—with Emma—along with the other surviving children, made their way to a train station that would take them to California, where it was rumored to be safer. However, once they reached the station they were ambushed by a force of Endarkened. With no time to even say goodbye, Julian and Emma shoved the Blackthorn children towards the train and ran at the Endarkened, holding them off long enough for the train to leave. At some point after this, Julian and Emma were taken to Sebastian and forced to drink from the Infernal Cup, becoming Endarkened themselves. This did not change their feelings for one another, and they remained together after the transformation.
Around seven years after Sebastian's victory, Julian and Emma's counterparts from another world arrived in Thule, and were present to witness the execution of Maryse Lightwood, which the Endarkened Emma and Julian attended, though they spent most of it engrossed in each other.
A few days later, the real Emma and Julian were caught out in the open and summoned by Sebastian, mistaken as the Endarkened versions of themselves. They went along with the ruse but failed to fool Sebastian, who pretended to be convinced and sent them back to the rebels in the hopes that they would find a way to open the Silent City.
When the rebels did make their move for the Mortal Instruments, Sebastian and his Endarkened, including Emma and Julian, were lying in wait. They proceeded to spring their trap after the Silent City was unsealed by Tessa Gray. In the ensuing battle, the Endarkened Julian was killed by his alternate self to save Livvy, who he had been threatening with a gun. The Endarkened Emma, grief-stricken, was left to weep over his body until Sebastian's death killed the remaining Endarkened, herself included.
- Queen of Air and Darkness (first and only appearance)