Baki is bored. After the conclusion of the epic battle between father and son, he continues to fight in the underground arena and train nonstop, but he always has to suppress his yawn caused by the overbearing boredom. No amount of stimulus or danger can bring excitement to him at this point.

Now, with the inclusion of the Prime Minister of Japan in the loop, a massive cloning project is attempting to clone Miyamoto Musashi, one of the fathers of martial arts in Japan. Another fight of historical proportions awaits Baki!

(Source: MangaHelpers)

There is three series of Baki, this one is Baki, the 2nd one.
1-Baki the Grappler(1991-1999) 42 volumes
2-Baki(1999-2005) 31 volumes
3-Hanma Baki(2005-12-05) ? volumes

Baki Hanma is a generally happy student with a rather odd hobby; he likes fighting. Specifically, he likes fighting in a secret martial arts tournament that gathers the greatest fighters of the world and pits them against each other in really nasty combat. Whether you're a sumo wrestler, a karate expert, or a guy who specializes in ripping out your opponent's nerves, you're welcome to participate (as long as you can keep quiet about it, of course). Anyway, Baki may be the youngest fighter the tournament has ever seen, but he's also the best, and he really enjoys what he does.

The sequel to the Baki series, supposed to concentrate around the conflict of Baki vs his father.

The story revolves around Baki Hanma and his quest to proclaim himself as the strongest grappler in the world, thus taking the title from his father. Baki also fights to gain the trust of his overly psychotic mother.
(Source: Wikipedia)

Spin-off series, written and illustrated by Miyatani Kengo, representing and describing Doppo's adventures.