Maki would basically be black paint. In that it would taint all of Mihawk's victories. Having a fighting ability that no other person on the planet can use would be cheating. If Mihawk found somebody who could overcome this Maki with pure swordsmanship, then he would probably be at peace. That, or somebody else who has discovered it independently.
u/EcstacyMeth2 — 12 days ago