Vimana

His Highness the King of Heroes’ mobile aerial weapon, which took flight for the first time in volume three. A high-tech Noble Phantasm from India that would even put Area 51 to shame. It uses solar energy produced by mercury-powered sun crystals to move. In ancient Indian mythology it came fully loaded with wondrous weapons ranging from ancient machine guns to ancient nuclear warheads, all of which are surely stashed away in the King of Heroes’ treasury.

Fate/Zero material: Fate/Zero Encyclopedia
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One of Gilgamesh’s “divine secret treasures” brought out from the Gate of Babylon. A golden ship recorded in the two Indian epic sagas of Ramayana​​ and Mahabharata. Made of gold and emeralds, and powered by solar crystals that use mercury as fuel to create solar energy. During the Mion river battle it dog fights Berserker’s F15 high up in the atmosphere.

Translator’s Notes
  1. ^ Throne of the Heaven-soaring King.
Fate/Zero Animation Guide II: Glossary of the holy grail war II