Isekai Tensei de Kenja ni Natte Boukensha Seikatsu: [Mahou Kairyou] de Isekai Saikyou

Minato dies in an accident and is reborn in a fantasy world where magic is poorly developed. He notices that magic circles are overly complex and spells are weak. Using his knowledge, he simplifies the magic system, increasing its effectiveness. He also creates a new, highly efficient form of magic. His intelligence allows him to surpass others in magical skill quickly. In a world where magic has faded, Minato is seen as a powerful and wise figure capable of controlling all elements. His journey of mastering and restoring magic begins.