1 (14)- "Hajimari wa totsuzen ni nano" ("The Beginning Comes Suddenly")(はじまりは突然になの)
Airdate: October 1, 2005
Nanoha, who is awaiting Fate's return, is ambushed by Vita and Graf Eisen for her Linker Core. Vita gains the advantage by using magical cartridges to increase her weapon's power. At the last minute when all seems hopeless Fate, Aruf and Yūno arrive.
2 (15)- "Tatakai no arashi, futatabi nano" ("Once Again, the Storms Battle")(戦いの嵐、ふたたびなの)
Airdate: October 8, 2005
Nanoha and Fate fight the much stronger Wolkenritter (Cloud Knights), and in the end Nanoha loses her Linker Core to the enemy while both Raising Heart and Bardiche are in severely damaged states.
3 (16)- "Saikai, soshite ohikkoshi nano!" ("Reunion and Relocation")(再会､そしてお引っ越しなの!)
Airdate: October 15, 2005
With what happened to Nanoha the Arthra crew has been assigned the mission of stopping the Wolkenritter, and with the Arthra being upgraded the captain's team consisting of Admiral Lindy, Chrono, Amy and Fate move into Nanoha's neighborhood for the time being. At the end of the episode Raising Heart and Bardiche demand a new and dangerous modification to their design.
4 (17)- "Arata naru chikara, kidō nano!" ("Our New Power, Start!")(新たなる力、起動なの!)
Airdate: October 22, 2005
Hayate's condition worsens, the TSAB corner the Wolkenritter in a barrier so Nanoha and Fate can take them on, to Nanoha and Fate's surprise Raising Heart and Bardiche begin a different Set Up. Amy tells them that their devices have been upgraded from Raising Heart to Raising Heart Excellion and from Bardiche to Bardiche Assault.
5 (18)- "Sore wa chiisa na negai nano (Zenpen)" ("It was a Small Wish (part 1)")(それは小さな願いなの (前編))
Airdate: October 29, 2005
Signum breaks into the TSAB barrier to help out her teammates with a fight soon following. Nanoha and Fate gain the advantage over their opponents, but a mysterious man arrives to help, and Shamal sacrifices some of the Book of Darkness's pages in order to destroy the barrier and allow the Wolkenritter to escape. It is revealed that the Wolkenritter are programs of the Book of Darkness.
6 (19)- "Sore wa chiisa na negai nano (Kōhen)" ("It was a Small Wish (part 2)")(それは小さな願いなの (後編))
Airdate: November 5, 2005
Signum and Shamal recall coming into Hayate's service, and how the love she showed them caused them to develop emotions. While she asked them not to fight, they eventually realized that unless the Book was completed, her life would be endangered, and decided to gather mana for that purpose.
7 (20)- "Kowareta kako to genzai to nano" ("With the Broken Past and Present")(壊れた過去と現在となの)
Airdate: November 12, 2005
Fate and Nanoha again confront Signum and Vita, trying to get them to reveal their motivations. The mysterious man protects Vita from Nanoha's attack, and then intervenes in Signum's fight with Fate, stealing Fate's Linker Core and incapacitating her.
8 (21)- "Kanashī ketsui, yūki no sentaku nano" ("The Decision of Heartbreak and the Courageous Choice")(悲しい決意、勇気の選択なの)
Airdate: November 19, 2005
Hayate's condition worsens, and she is hospitalized after collapsing at home. The TSAB realize that the Book of Darkness is going to kill Hayate upon its completion. Nanoha and Fate visit Hayate in the hospital through Suzuka, a mutual friend.
9 (22)- "Kurisumasu ibu" ("Christmas Eve")(クリスマス·イブ)
Airdate: November 26, 2005
Chrono continues his research on the Book of Darkness. On Christmas Eve, Nanoha and Fate give Hayate a surprise visit, and encounter the Wolkenritter in the hospital room, learning of their connection to her. The groups fight that night on the hospital roof, but two masked men intervene, drain the Wolkenritter's Linker cores and summoning Hayate to the roof while disguised as Nanoha and Fate, and kill Vita in front of her to force her to awaken the Book of Darkness.
10 (23)- "Unmei" ("Destiny")(運命)
Airdate: December 3, 2005
Hayate is engulfed by the Book's power. Chrono fights the masked men and discovers that they are the Lieze Twins, Admiral Graham's familiars, and that Admiral Graham had planned for Hayate to complete the Tome of Darkness in order to seal it and her away. While Arisa and Suzuka learn the truth about Nanoha and Fate, Fate gets absorbed by the Book of Darkness.
11 (24)- "Seiya no okurimono" ("A Gift For Christmas Eve")(聖夜の贈り物)
Airdate: December 10, 2005
Fate is trapped in a dream of an ideal life with Alicia and a sane Precia, but manages to break free and then activates her full drive Zanber Blade. While on the outside Nanoha activates her full drive Excellion Mode despite the fact that it could destroy Raising Heart. Hayate reaches out to the Book of Darkness, renaming it Reinforce and becoming the first person to wake up when the Book of Darkness had been completed.
12 (25)- "Yoru no owari, tabi no owari" ("Night's End, Journey's End")(夜の終わり、旅の終わり)
Airdate: December 17, 2005
Hayate regains control of Reinforce, and revives the Wolkenritter. The Wolkenritter and Hayate team up with Nanoha's group to defeat the corrupted defense program of the Tome of Darkness.
13 (26)- "Sutanbai redī" ("Stand By Ready")(スタンバイ·レディ)
Airdate: December 24, 2005
Although the danger is averted, the potential for the corruption to return remains, and Reinforce gives up her existence in order to prevent that. Hayate and the Wolkenritter join the TSAB, and Nanoha tells her family about what she has been doing as a mage. Six years later, Nanoha, Fate and Hayate are in middle school, with Hayate having a second Reinforce by her side.