More and more people arrived from every corner of the Prima Universe to the void outside the Realm of Madness. Many of them were geniuses considered the core of the universe's next generation, so it was no wonder that even Issac and Salomon focused on the Omega Law containing them.
The Magus Primarch stood alongside Bahamut and many other powerhouses outside the Leviathan World. They have entirely sealed space-time in the void around the world, making it impossible for anyone to enter or leave.
Even the Leviathan Primarch could not exit the world without Issac detecting him. Of course, Jormungandr could forcefully break the seal in space given enough time, but he would have to leave the Leviathan World and face the Magus Primarch in the void.
Issac had always been stronger than Jormungandr. Since the latter had yet to recover from having his body and soul destroyed by the Incarnation of Death and Destruction, the fight's outcome was obvious.
