Without breaking the formation, getting out of here was impossible.
He already had a bit of formation knowledge which he had received from the bloodline temple. Even though he hadn't practiced that knowledge to make any formations other than a few changes in the mask of mischief formation, theoretically, he was knowledgeable.
And with that knowledge, he realized that those kinds of large-scale formations that could take over a whole city had many formation points since they needed a lot more energy than a small-scale formation would.
And according to his assumptions, most of those formation points should be right around the Royal City at the edge, most probably. Through the strange lines in the sky, he believed that it was possible to find these ones.
But the tricky part was finding the ones that could have been made inside the city as a backup. This guy was certainly not going to be stupid enough to leave all the cards in one deck.
