"Better than nothing," he spent a couple of days doing so, as most of the monsters were either buried under heavy rocks, or were thrown far away from here.
As he was the one to cause the falling rocks and that disaster back then, he was able to devour these cores. And yet he found many that he couldn't, guessing that these were the ones killed by Sloth and other masters when they were here.
"I should head to check one black hole then," William had nothing else to do. The masters were having a great time exerting their revenge, and so it was time for him to check his ticket back to his world.
He didn't intend to go back right away, not before he'd make sure the glory of this grand and epic victory would be appointed to his guild.
He first spoke with Sloth. He asked about the current status of the war, and told him about his intentions.