Reinhard van Astrea

The Sword Saint, named by the author as the strongest character in the series.

Reinhard van Astrea is an easygoing knight of the Royal Guard who holds the title of Sword Saint and quickly becomes friends with Subaru. He is stronger than every Sword Saint before him.

Quick Facts

Title: Sword Saint
Serves: Felt (royal election)

Facts from the source article.

Background

His edge is a unique ability to produce magical counters to whatever an opponent uses, past or present. When Emilia's insignia reacts to Felt, Reinhard becomes Felt's knight for the royal election. The author has said outright that he is the most powerful character in the world of the series.