OVAs of History’s Strongest Disciple Kenichi bundled with volumes 46, 47, 49, 53, 54, 55, & 56 of the manga.
Soon after Kenichi’s defeat of Ragnarok, the Ryozanpaku masters find out about an aliance between some of their enemies. Now the entire Ryuzanpaku dojo, both its masters and students, find themselves targets of powerful martial artists. To Kenichi’s dismay, this also means his training also becomes a lot harsher. Spurred on by Kenichi’s growing strength, the former Ragnarok members also begin to seek to improve their fighting styles.