Sealed Armament: Izayoi

The Sealed Armament: Izayoi (封印兵装・十六夜) is an Ars Armagus wielded by Tsubaki Yayoi, and previously by Ayame Yayoi during the Dark War.

Information
The Izayoi is kept under a special lock that can only be opened from the blood of a person from the Yayoi family. Tsubaki needed the Izayoi to combat both Jin Kisaragi and Noel Vermillion, since they both possess Nox Nyctores-class weapons. The Sealed Armament: Izayoi takes the form of clothing, gives her sword resembling a quill tip and a book-like shield; however, it can change its shape for some of Tsubaki's attacks. It also has a different true form.

Created long ago to fight the Observers, it served as a model for the Nox Nyctores that were produced later. The Sealed Armament: Izayoi is actually the Murakumo Unit prototype. The first known Murakumo Unit was produced before the Dark War and along with Prime Field Device Type Zero and Azure Grimoire, was used to create the first Kusanagi.

The Sealed Armament: Izayoi raises the user's power by several times in exchange for their "light". Due to this, using the weapon for an extended period of time will cause the user to go blind, or in the worst case, it will cost the user's life. Along with its wielder's light, it draws in all waves within the electromagnetic spectrum, including the radio waves received by Tager's radio, allowing the weapon to interfere with radio signals. As its true power is the complete absorption of a specific wavelength of light, serving as an Anti-Observer Weapon (対観測者用兵装). It can even fully neutralize Phenomenon Interventions. Any wielder of the Izayoi is capable of deploying the Zanki Barrier, an extremely powerful Ars Magus that creates a space that is completely separated from the outside world.

While the Sealed Armament: Izayoi is a "shield" capable of warding off intervention, its released form, Zero-Type: Izayoi (零織・イザヨイ), is a "lance" with the power of the Immortal Breaker, the ability to slay "those that are outside of logic", such as Rachel Alucard. Specifically, the Immortal Breaker places death in the mind of its target. However, it is incapable of piercing those with the Power of Order, such as Jin Kisaragi.

Trivia

 * "Sealed Armament: Izayoi" has three different localizations. During BlazBlue: Continuum Shift it is: "Sealed Weapon Izayoi" and once "Sealed Armagus Izayoi". Since BlazBlue: Chronophantasma, it is alternately: "Sealed Weapon Izayoi" and "Sealed Armament Izayoi".
 * In Tsubaki's bad ending in BlazBlue: Continuum Shift, she dies due to the overuse of the Sealed Armament: Izayoi, as she mentioned that she already knew that it will take her life. However, it was just one of the possibilities of the Continuum Shift. In Noel's arcade mode, when she faces Hazama, he comments on how Tsubaki's strength is "fading", implying that eventually the Izayoi may kill its wielder if used too much.
 * The name Izayoi means "sixteen-day-old moon" in Japanese. A sixteen-day-old moon has just passed its fullest phase, so it is at this point that its brightness begins to decline. This is another clear reference to Izayoi's blindness-inducing nature.
 * Hakumen was the one that implored research of the Izayoi.
 * Zero-Type: Izayoi's portable form is similar to Lux Sanctus: Murakumo, although instead of being a big sword, it is a big shield with a pike encased in it.
 * There is a visible "00" mark on Zero-Type: Izayoi's portable and armor form, representing that it has been chosen as the Murakumo Unit's prototype.