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"Declaration of War" (宣戦 Sensen?) is the 98th of the Toaru Kagaku no Railgun manga series, released on October 27, 2017. This chapter formally opens the Jailbreaker Arc.

Academy City's second reformatory opens with an open challenge to any interested esper: break into the facility, retrieve the prisoner inside, and make it out. With a staggering reward of one billion yen to be given to the one successful in the challenge, Mikoto, Kuroko, Saten and Uiharu join the event with their own insights about the jailbreak event.


Mikoto, Kuroko, Saten and Uiharu find themselves with many other participants in front of what was announced to be Academy City's second juvenile hall. Director Kyougoku, who owns a private security business, decided to open the second juvenile hall in response to a rise in crimes committed by espers as opposed to those involving Skill Outs. Confident that a private firm would provide better service compared to Academy City's publicly-run juvenile hall, Director Kyougoku invites interested espers to test the security features of the newest reformatory—basically a jailbreak trial—by breaking into the facility, finding the target prisoner, and breaking out of the facility itself. The person who successfully extracted the prisoner from the facility will be rewarded with one billion yen.

Saten decided to join the competition for the handsome reward, but both Uiharu and Kuroko see the event as a way to show off the new facility's defense mechanisms. Regardless, Kuroko chose to join to watch over Mikoto's actions. Meanwhile, Mikoto wanted to participate for a change of pace. However, listening to Director Kyougoku boasting about the lack of capabilities of Tokiwadai's espers for the challenge has somehow urged Mikoto to join the jailbreak event.

Major Events

  • A private juvenile hall, supervised by Director Kyougoku, opens with a jailbreak trial to showcase its defenses against espers.


By order of appearance:

New Characters


No abilities were used in this chapter.




  • Just like the publicly-run Reformatory, the second juvenile hall is also equipped by AIM Jammer units. The units installed in the second juvenile hall, however, towers at 15 meters in height.

Unanswered questions

  • Who is the person that they'll be breaking out?
  • Who is the person next to Mitori wondering about Misaki?


  • Director Kyougoku: "Even if a powerful school with multiple Level 5s...that is, even if Tokiwadai Middle School gathered every one of their students...I doubt they could even breach the first wall. Oh, my apologies! Bragging that we can stop some rich girls who have not even completed their compulsory education isn't saying much, is it!?"



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Toaru Kagaku no Railgun
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Volume 4 181920212223
Volume 5 24252627282930
Volume 6 31323334353637
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Volume 8 4546474849505152
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Special 17.524.525.542.596.5122.5