- 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.
When Sebastian Morgenstern attacked the Los Angeles Institute, Emma's parents were killed while she managed to escape with the Blackthorn children. During Sebastian's invasion of Idris, Emma and the Blackthorns were among the young Shadowhunter children sent through a Portal to a shelter in New York for their safety.
Not long after their escape, Idris fell to Sebastian and his army, and the rest of the world slowly followed as demons became more rampant in the world due to Sebastian's doorways, which also affected the warlocks who helped them. Two months later, the shelter in New York was destroyed, forcing Emma, the Blackthorns, and the remaining children into the streets. At one point during this, Emma and Julian began dating.
Emma and the Blackthorns 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. Emma and Julian urged 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 witnessed 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 other-world 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, whom he had been threatening with a gun. This Emma was grief-stricken and wept over his body until Sebastian's death killed the remaining Endarkened, herself included.
- Queen of Air and Darkness (first and only appearance)