Sapphire Weapon (サファイアウェポン, Safaia Wepon?) is one of the seven Weapons created by the Planet, and one of the five in Final Fantasy VII roused to protect the world following Meteor's summoning. It seems to be aquatic and can shoot a laser from its mouth. It is the only Weapon that cannot be fought by the party.
As the Sapphire Weapon is never fought in the game, it is never named in Final Fantasy VII. It is identified as Sapphire Weapon in official materials, including a Final Fantasy Art Museum card in 2001, a figurine released in 2004, and Ultimania guides.
After Meteor is summoned and Tifa awakes in Junon, Heidegger reports to Rufus that a Weapon is approaching from the sea. When Sapphire Weapon reaches the shore, it surfaces from the water and rears its head in front of the city, only to have it blown off by the Mako Cannon.
Sapphire Weapon appears as figurines in the Final Fantasy Creatures Vol 4 series that came out in 2004. The Final Fantasy Creatures collection figurines require minimal assembly and there are three types of every character: full-color, crystal, and chrome.
Sapphire Weapon is mentioned in Lunafreya Nox Fleuret's chapter, which tells the story Episode Luna would have covered had the second season of DLC not been cancelled mid-way. It can thus be presumed that the Sapphire Weapon was to be the final boss of Episode Luna. Sapphire Weapon is a magitek weapon similar to the Diamond Weapon hidden away in ancient Solheimian ruins on Niflheim territory. When Aranea Highwind heads there to investigate, she ends up being trapped there amid daemons. Sol and Lunafreya team up to rescue her, and find the Sapphire Weapon and destroy it.