Black Knight is a major character in Yu-Gi-Oh! ReWrite. Not much is currently known about him.
STILL IN PROGRESS
In the first chapter, Black Knight faces off against Yuzuki Taiga after the former invades the Security Offices and gets away with a possession of Yuzuki's.
Black Knight, matching his namesake, uses a "Black Knight" Deck, focusing around DARK Warrior-Type monsters and Synchro Summoning. His main strategy involves getting his monsters into the Graveyard to use the effect of his ace monster, Black Knight of Destruction - Absolute Ruin, to burn his opponent.