The bomb is a circular device that is black with blue glowing accents around it. It is shown to be much larger than a multiple of FRANXX grouped together.
The bomb was built presumably tens of millions ago in correspondence to the war with VIRM, and it was kept hidden within the Klaxosaur Mothership after VIRM retreated and the surviving Klaxo Sapiens went into hiding in Earth’s core.
The bomb was discovered when the mothership was destroyed during Squad 13’s battle with VIRM In Mars’ orbit. Strelizia True Apus took the bomb and entered a Warp Gate to eliminate the VIRM home planet, and end the war. This journey would go on for two years until they reached their destination. VIRM almost succeeded in destroying the bomb after severing Hiro and Zero Two’s connection in Strelizia but the two overcame VIRM by implanting the bomb onto the planet’s surface and activating it by flying directly into a crevasse in the bomb, which destroys any trace of the planet.