Shishio Makoto Vs Baki Hanma, Kenichi Shirahama & Ohma Tokita
The martial artist protagonists of Baki, Kengan Ashura & History’s Mightiest Disciple set their sights on arguably the greatest antagonist in anime history and the second greatest Hitokiri in history. (Rurouni Kenshin)
The three martial artists fight him in a standard dojo and can decide how to fight him.
This is all characters as they appear in their stories, no post story implied feats. (Kenichi in particular)