Izuna

Biodata

Background / History

Izuna grew up amid the Uchiha–Senju feud. His older brother and two younger brothers died during the period when shinobi clans freely attacked one another’s children. He later explains that members of both clans had seen their loved ones tortured to death, allowing him to understand Tobirama’s hatred despite their hostility 43.

At eight, Izuna first fought Tobirama directly at the Naka River. During their clash, Izuna’s father and Butsuma Senju each threw a blade at the opposing child’s vital points, accepting the possible loss of their own son as a worthwhile exchange. Madara and Hashirama intervened and saved both boys 43.

After Madara and Hashirama became clan heads, they prohibited killing other clans’ young children. Izuna credits this rule with easing the hatred between the Uchiha and Senju over the following decade 43.

Appearance

• Hair and features: Long black hair and a stern face closely resembling Madara’s, distinguished by an even sharper gaze 1 10 13.
• Clothing: Wears dark traveling clothes without armor during his visit to the Hagoromo encampment 9.
• Weapon: Keeps a sword at his waist, frequently resting his hand on its hilt when threatening someone 1 2 9.
• Sharingan: Displays a three-tomoe Sharingan while reprimanding Setsuna 24.
• Wartime fatigue: Develops dark circles after several sleepless nights supporting the Hagoromo 36.

Personality

Izuna is sharp-tongued, intimidating, and fiercely loyal to Madara. He threatens Setsuna at their first meeting and repeatedly punishes insults against the clan head. Around his brother, however, his sternness gives way to open affection: he rushes to greet Madara, struggles to hide his smile, and becomes embarrassed when others witness it 2 24 36.

Although identified as the Uchiha hardliners’ leader, Izuna can place survival ahead of revenge. He urges the Hagoromo clan leader to abandon a counteroffensive that would expose the clan to annihilation. When asked to decide the Hagoromo’s course, he limits himself to advice rather than claiming authority over another clan’s survival 11 21.

His treatment of Setsuna combines strict discipline with genuine protectiveness. He appreciates the child’s combat instincts and compares his disobedience to Madara’s younger days, but refuses to let him remain exposed to danger merely because his schemes are useful. He also quietly cares for Setsuna when the boy falls asleep or is injured 9 23 24 42.

Izuna’s radical reputation does not extend to overthrowing the Daimyo. Setsuna’s proposal shocks him, and he initially defends the ruler’s supposed divine ancestry and ability to commune with gods 44.

Abilities & Skills

Swordsmanship

Izuna is known as the “Warring States’ Greatest Swordsman,” with a fighting style built around overpowering enemies directly 2 22.

• Trains his swordsmanship into conditioned reflexes so that he can fight without relying on sight against Tobirama’s Bringer-of-Darkness Technique 34.
• Can meet Tobirama head-on despite the disadvantage of Fire Release against his opponent’s water nature 34.
• Practices the mental composure needed to remain calm when drawing his blade 10.
• Acknowledges that he cannot confront twenty Fuma jonin alone and must retreat without additional support 13.

Sharingan

Izuna possesses a three-tomoe Sharingan and takes pride in the Uchiha’s ocular abilities 24 47.

• Participates in operations where Uchiha Sharingan users pinpoint enemies located through the Hagoromo’s broader detection abilities 23.
• Plans for Uchiha jonin to use the Sharingan’s dynamic vision to hunt independently inside the Hagoromo barrier 14.
• Proposes layering Uchiha genjutsu over the barrier to conceal its danger and make the territory appear vulnerable 14.

Fire Release

His Fire Release is known for overwhelming power, alongside his swordsmanship 22.

• Helps develop a joint tactic in which Hagoromo spatial distortion amplifies Uchiha fire techniques into Blast Wave Wild Dance 13 14.
• The proposed combination compresses and redirects flames, multiplying their power and range 14.
• This is a cooperative strategy requiring Hagoromo control of space, not a demonstrated independent spatial ability of Izuna’s 14.

Battlefield Command and Intelligence

Izuna coordinates reinforcements, evaluates enemy strategy, and represents Uchiha interests in negotiations 9 13 23.

• Uses Setsuna’s Uchiha–Hagoromo ancestry and prospective heirship as a concrete pledge of the alliance’s future 9.
• Assigns reserve Hagoromo fighters to replace exhausted barrier maintainers, preventing gaps in the formation 14.
• Anticipates that Tobirama may sabotage negotiations by spreading distrust among the Fuma or occupying Blood Horse territory 23.
• Judges that sharing Cloudfield would invite continued sabotage between the Senju and Hagoromo 43.

Equipment / Items

• Sword — His constant weapon, carried at his waist even when he travels without armor 9.
• Uchiha command token — A bamboo token engraved with the Gunbai emblem, entrusted to a messenger summoning reinforcements 13.
• Maps and intelligence scrolls — Used to assess neighboring clans, enemy movements, and proposed settlement terms 12 23 43.

Relationships

• Madara Uchiha — Older brother and clan head. Izuna follows his assignments, defends his authority, and takes pride in his ability to keep Hashirama occupied 9 21 24 36.
• Uchiha Setsuna — Young relative and prospective clan heir. Izuna becomes his protector, disciplinarian, and instructor, ultimately voting for his succession after observing his performance 2 24 43.
• Tobirama Senju — Lifelong nemesis and battlefield rival. Their hostility dates to childhood, though Izuna understands the family losses behind Tobirama’s hatred 2 34 43.
• Old Hagoromo Clan Leader — Maternal uncle and allied leader. Izuna advises him against a disastrous offensive and helps organize the territory’s defense 11 14.
• Hagoromo Shōgatsu — Strategic collaborator. They discuss threats to the peace talks and work within the joint Hagoromo–Uchiha defense 21 23.
• Toshihi — Uchiha subordinate who reports Setsuna’s battlefield conduct and carries out Izuna’s arrangements for the child’s return 9 24 25.
• Hashirama Senju — Enemy clan head who helped save Izuna at eight. Izuna recognizes the importance of the child-protection rule Hashirama and Madara later established 43.

Story Role / Major Arcs

Setsuna’s Heir Candidacy

At the clan meeting, Izuna initially insists that Setsuna must survive battlefield service before being considered for succession. He offers his vote if the boy performs well on a supply mission 2.

After learning that Setsuna and Kagami killed two Fuma chunin, Izuna responds favorably to the boy’s talent despite his disobedience. He then plans to announce Setsuna’s future heirship to the Hagoromo as a means of strengthening the alliance 9.

Defense of the Hagoromo Territory

Izuna accompanies Setsuna to the Hagoromo clan leader and argues against a counteroffensive while the Senju, Fuma, and Blood Horse threaten the clan. He also identifies a route for Setsuna’s proposed grain-wagon scheme 11 12.

When Fuma forces breach the territory’s defenses, Izuna evacuates Setsuna. The boy’s suggestion to combine Hagoromo intangibility with Uchiha techniques persuades him to return, summon reinforcements, and present the ambush plan to the old clan leader 12 13 14.

Izuna claims the idea as his own. The old clan leader recognizes that he is shielding Setsuna from attention that could make the gifted child a target 14.

Negotiations and Setsuna’s Protection

As negotiations replace intensive fighting, Izuna remains with the Hagoromo as a deterrent against Tobirama. He sends Setsuna home, explaining that the child needs time to grow and prepare for possible succession 24 25.

When Madara arrives, Izuna defends the Uchiha’s contribution to the war and recognizes the advantage of waiting for Hashirama to act before intervening 36.

Lessons on War and Political Authority

Izuna recognizes Setsuna’s intention to kidnap Naoki Senju before Madara rejects it. After Setsuna’s punishing training fight, Izuna cleans his face and carries him away 41 42.

That night, he explains the childhood tragedies behind the prohibition on attacking young children and gives Setsuna intelligence to study. Their discussion develops into an examination of shinobi strength and the Daimyo’s authority, culminating in Setsuna’s proposal to overthrow the ruler 43 44.

Threatened Future

Setsuna’s memories identify Izuna’s expected death as the result of Tobirama’s Flying Thunder God Slash. Having come to regard Izuna as a comrade, Setsuna resolves to reject that future 2 32.

During the Naka River ambush, Setsuna suspects Black Zetsu intends to kill Naoki, restart the Uchiha–Senju war, and place Izuna in a fatal situation to hasten Madara’s despair. This remains Setsuna’s interpretation of the attack 49.

Notable Quotes

“You're only five and a half. You still have room to grow. I don't want you exposing yourself to danger too early.” 24

“I can only offer advice. I can't directly interfere in a decision that determines whether your clan survives.” 21

“So I can understand why Tobirama Senju hates us so much. Because our loved ones were tortured to death by them just the same.” 43

Trivia

• Izuna’s game incarnation is A-rank. Its high-speed dashes and consecutive close-range slashes earned the player nickname “Biting Style Ancestor”; this ranking describes the game character, not an advancement in the novel’s present storyline 2.
• He briefly mistakes Setsuna’s miko disguise for a Hagoromo girl and considers arranging a match for Setsuna before recognizing him 41.