https://megaman.fandom.com/wiki/Fairy_Leviathan

Fairy Leviathan

"Playing 'hero' must be a fun way to pass the time..."
—Fairy Leviathan

Fairy Leviathan, known in the Japanese version as "Youshou" Leviathan (「妖将」レヴィアタン 「Yōshō」Reviatan, Yōshō literally meaning Siren General), or simply Leviathan, is a member of the Four Guardians of Neo Arcadia in the Mega Man Zero series. She was created from Mega Man X's DNA data after the Maverick Wars to clean the world's oceans. Leviathan's schematics are based off X's capabilities of underwater combat. Some time later, she became a military general of Neo Arcadia, commanding the Deep Sea Squadron (冥海軍団 Meikai Gundan, literally "Army of the Dark Oceans"), Neo Arcadia's navy force. Leviathan wields a spear, named Frost Javelin (フロストジャベリン Furosuto Jaberin). In the Mega Man ZX series, she makes an appearance as Biometal Model L.