Name: Mugen
Age: 19
Profession: Vagabond, and former Pirate
Weapon(s): Double-edged katana (in the videogame, Samurai Champloo: Sidetracked, this sword is named "Typhoon Swell"), Tanto (concealed in opposite end of scabbard)
a claymore at the end of the series

Fighting style(s): mix of various styles incorporating rapid, irregular movements he dubs "Champuru Kendo"
Quote: "I don't give a rat's ass about going to hell. I guess it's because I feel like I'm already there!"
Appears in: All episodes
Final status: Alive

Mugen (無限) was born in a penal colony on the Ryukyu Islands (possibly in Okinawa), which in the Edo period was a separate kingdom with close ties to the Satsuma domain of Japan. His name means without limitation, as the components of it are the characters for "without" and "limitation." Incidentally, he writes his name using the infinity symbol (∞), a pun on his name, 'Mugen,' which is a homophone of the Japanese word for 'eternity'. His Japanese is quite rough and "Yanki"; and he is illiterate until later in the show.

The exact date of his birth is unknown, and much of his past is shrouded in mystery. Mugen states that he never knew who his parents were in episode 20, "Elegy of Entrapment, Verse 1." The blue tattoos on his wrists and ankles indicate that he was once in prison.^[1] The circumstances of his imprisonment are unclear at first, but it is later verified that he was to be executed for engaging in piracy.

Rude, lewd, vulgar, and nihilistic, Mugen is somewhat of an antihero. Some of his actions seem to represent an amorality, indicating that he operates more on instinct than anything else. Character designer Kazuto Nakazawa stated in an interview: "When I was doing character design, the most difficult one was Mugen, as I expected. I'm pretty sure that as far as the director's image went, he probably was thinking of someone like a 'rapper who acts like a bad guy.' But the way Mugen acts is relatively based on his core conviction."^[2] He and Jin fight from time to time, but there is an undercurrent of mutual understanding between the two. Despite periodic confrontations with Fuu he also seems to care for her, staging rescues of her on several occasions.

Highly unorthodox swordplay and a fighting style based on breakdancing - dubbed "champuru kendo" and ostensibly developed by himself - make him a force to be reckoned with. ^[3] His fighting style is probably best described by Kariya Kagetoki when they fight in Episode 25: "Interesting. You utilize erratic movements to prevent anyone from predicting them. But you fail to utilize your martial arts skills. By relying only on reflex and instict, you inadvertently show the limitations of your skills to your opponent." This is further evident in that his moves become increasingly erratic and unique as his opponents are more powerful. He carries two blades, his principal weapon a unique sword sheathed across his back and the other a small tanto concealed at the end of his scabbard (only resorted to as a trump card). Mugen also has a tendency to parry attacks with the steel base of his geta. His clothing is anachronistic as well, reminiscent of baggy hip-hop fashions of today: his gi functions more like a jacket and his hakama is cut off at shorts-length, resembling loose-fitting Bermuda shorts. His black hair is unkept and similar to an afro or Spike Spiegel's, being one of a number of similarities he shares with Spike. Coincidentally int the English dub Spike and Mugen share the same voice actor as one another.

Mugen seems to be incapable of dying, or at the very least has a body that is more resistant to life-threatening injuries than the average person. When on the verge of death, he appears to cross into a mystical world in the Ryūkyūan religion called Nirai Kanai—depicted in Samurai Champloo as an upside-down mirror world—overseen by the Futuchi who are dressed in black-feathered robes and carry spears. With each visit to this world he is subsequently 'rejected.' He has been brought back to life in this manner on at least three occasions. It has been speculated that his survival is because he is being preserved for a greater purpose.

It is unclear as to how Mugen feels about Fuu since it is difficult to know what he is thinking. However, there are some cases in which involves Mugen's feelings with Fuu. In Episode 25 when Umanosuke took Fuu hostage, he said to Mugen that neither one cared for her life. Mugen did not deny it nor did he agree, only spatting "Shut up!" at Umanosuke. Also, in Episode 24 when Fuu was speaking with Jin by the river, she mentioned Mugen's name but did not finish what she had started to say. Mugen, who was nearby, had overheard the conversation, his face expressing mixed emotions. Many females made appearances throughout the series, but Mugen's attitude towards them were different than how he was to Fuu. The only other female that Mugen was much calmer with was Kohza, a girl he knew before the journey. Perhaps it was because Fuu and Kohza had a significant impact on him that he acted differently with them, maybe even because they were women he felt comfortable with without any sexual tension. At the end of the series there are no specific conclusions, but it is likely that Mugen may care about Fuu in some way.

His seiyū is Kazuya Nakai. His dub actor in the U.S. version is Steven Jay Blum, credited as Daniel Andrews to circumvent union regulations