Gigant: Takemikazuchi was a form of satellite and the largest Nox Nyctores to have been created. According to BlazBlue: Continuum Shift, it was sealed away after the war due to fear of its use. Despite this, the satellite was still activated and had fired upon Kagutsuchi in BlazBlue: Calamity Trigger. From Rachel's words, it seems as though Takemikazuchi could only fire once every four years.
The weapon first appears in the opening to BlazBlue: Calamity Trigger, where it fired upon the 5th Hierarchical City of Ibukido and destroyed the facility where Mu -No. 12- was being tempered. In one timeline, this act killed her, but in another timeline, the one in which BlazBlue's story mostly takes place, she survived but has no memory of the incident. In BlazBlue: Phase Shift 2, while Hakumen fought the Black Beast to protect Celica, Seven and Eight deployed it against the Black Beast after stealing a portion of Celica's power (thus making her faint in the middle of the battlefield) which allowed them to control the creature.
Although Nine laid out its foundations, it was mostly developed by Seven and Eight. As Konoe perceived it as a mistake, she advised them to cease its development. When they revealed that they require Celica's power in order to complete its control system, Nine ordered them (as the one with absolute authority) to dispose of it completely.
In BlazBlue: Chronophantasma, Takemikazuchi is the final boss in Story Mode, summoned from space by Hades: Izanami. Since Relius had opened all the Gates, causing the surface to be much thicker with seithr, it could fire as and when it likes, rather than once every 4 years. It took Jin, Noel and Ragna with his BlazBlue activated to defeat it. After its defeat, Hades: Izanami merged Takemikazuchi with the souls gathered from the Monolith. Takemikazuchi is now part of the new Embryo floating above the ruins of the 5th Hierarchical City of Ibukido.
In the story mode gameplay, the player plays as Jin first, followed by Noel and finally Unlimited Ragna. It is a fearsome opponent to defeat, having attacks that are sudden and possibly unblockable, and has Hades: Izanami frequently backing it up with attacks of her own. In Overdrive state, Hades: Izanami summons three purple homing energy spheres as well as three portable turrets, similar to Mu's Steins Gunner, firing in quick succession at the player, but can be destroyed (slightly difficult since they move after firing before almost immediately firing again). The huge beams which Takemikazuchi usually fires are its two Distortion Drives, but both can be fully avoided. Moreover, it also has an Astral Heat of its own, in which Hades: Izanami summons a red beam from the ground, before multiple blades, similar to Nu's, are shot upward where the player is then trapped by chains with blades and then fired upon by Takemikazuchi. At the end of the story mode, a new mode is unlocked which allows the player to fight Takemikazuchi again but with any character.
Takemikazuchi is the name of a Japanese thunder god, who is also the patron saint of warriors. His name means: "Fierce-Earth of Three Days".