Lunar Shiva is an optional boss in Final Fantasy IV Advance and The Complete Collection. She is fought during Edward Chris von Muir's Lunar Trial at the Lunar Ruins. When beaten, the player obtains the Harmony Ring, which changes Edward's Sing command to Chant, and the Grimoire LS which, if used as an item, summons Lunar Shiva to deal 9,999 Ice-based damage to all enemies. Using up the Grimoire unlocks the trial door again.
Lunar Shiva attacks using physical strikes and Blizzaga, as well as Frost Blast, which hits the entire party for mediocre damage. She does not counterattack, but will counter spells by casting Blizzaga on herself to heal for approximately 3,000 damage. She extends her staff and casts Icestorm, dealing high damage to the entire party; however, this damage is based on her HP and will decrease as she is damaged.
Luna means "moon" in Latin, Italian, Romanian, Russian, and Spanish.
Shiva (also spelled Śiva) is a Hindu god. The Hindu Shiva once saved the world by consuming poison, giving him blue skin around the area of the neck and throat. Shiva is a male god, but can merge with his consort Parvati to become Ardhanari, an androgynous Hindu god of duality. Shiva is the god of destruction along with Vishnu, who is the god of preservation, and Brahma, the god of creation. Together they are the three principle deities of the Trimurti (Hindu Triad). It is believed he periodically destroys the world, then recreates it.
Shiva has different human forms, males and females. When he was in his avatar form, he spent most of his times in the Himalayan snow mountain. Shiva in the Final Fantasy series is likely inspired by one of his female avatars.