When a grand magus dies, their spirit can escape from their body, but their aperture remains within the corpse. This means that even if they manage to inhabit a new body, without their aperture, they lose access to their domain and, consequently, their grand magus power. These apertures, which store all the grand magus's possessions, become the main prize for the victor—provided they can successfully enter without destroying it.
Emery had read about the challenges and intricacies of accessing an aperture. Knowing Mo Yan's many infamous criminal activities, Emery was particularly motivated. He hoped to find a substantial collection of valuables inside. Given Mo Yan's proficiency in darkness elements, Emery anticipated discovering numerous darkness-type materials that would be highly beneficial to him.