Ruling the Infinite Worlds with the Overlord System

Another Einstein with the brains successfully unraveled the mystery of his grandfather's last puzzle that remained unsolved for ages.
Wow! Longevity Medicine.
The whole world wants it, all super powers fighting for it but he didn't want to release it to the world.
BOOM
He dies.
Join me as we check his reincarnation journey in another fantasy world different from earth where he is not bound by law because HE IS THE LAW.