As Arad took a seat on Isdis's throne, he could feel a powerful surge of her divine magic. He was getting linked to the entire heaven through the throne, and for some reason, he could act as a better conduit than even Isdis herself. The amount of divine magic he was used to pulling out of Kali was far larger, so handling this wasn't bad at all.
He wasn't using Isdis's divine magic, just acting as a conduit, a central pillar that the divine power uses to spread all over the heaven. And the moment Arad took over, the entire planet shook. Unlike Isdis, Arad was able to let a far bigger current of divine magic out, and even spread it evenly across the planet since everything was already located in the vast space of his stomach.
