As with the formation of his Aether Core, as soon as Reiga's first beam was produced Jake used all his willpower and radiation control to force the beam to bend. Its wave-like behavior made the process exceptionally difficult, but Jake had been preparing for this eventuality from the start.
Jake had achieved enough control over the ambient light to make himself literally invisible even before the Fourth Ordeal began. By contrast, forcing the light to follow a certain path was no big deal.
This constant beam of Reiga curved again and again, until it formed a ring that circumscribed the Aether Symbol within. Within seconds, this ring quickly grew in brightness, but because its light was trapped and the diameter of this ring so small, all a curious onlooker dissecting its insides would have found was a tiny black hole.