I'M The Only Magus In This Witch World (m.webnovel.com)

Eating neutron stars as snacks and drinking wine distilled from 4 galaxies, the God of Games, at the peak of existence, had grown bored. No longer finding entertainment in reincarnating others, he decided to reincarnate himself into another world, sealing away all his powers to cure his boredom. But things didn't go a…