The Beginning After The End Episode 1

Grey, the strongest king in history, is the protagonist of the tale. Despite his unrivaled fame, fortune and power nobody supports him... and he doesn't trust anyone. One day Grey dies unexpectedly and reborn in a magical world as Arthur a helpless baby. Arthur begins to discover joys in a new life that he was unaware of on his old one surrounded by a loving family and friends. But his family was assaulted by bandits while traveling. And Arthur want to become the powerful mage He secretly trains with a mysterious man named Basho, learning magic and combat skills, pushing his limits and becoming stronger.