GUDAGUDA Mysterious Tales of the Imperial City's Holy Grail 1945.
http://news.fate-go.jp/2018/teito/
Full song:
Song title : 二者穿一
Singer : 歌:六花
Lyric : 毛蟹(LIVE LAB.)
Composition/Arrangement･編曲:西岡和哉
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From Koha-Ace:
The Mysterious Tales of the Imperial Capital Holy Grail (帝都聖杯奇譚, Teito Seihai Kitan?) is a divergent Grail War set during the time of the Third Holy Grail War.
The Imperial Japanese Army won the war and created a new bomb that used the Holy Grail as its core. Called the "81st Holy Grail Bomb", it is a special weapon designed to protect Japan against its enemies near the end of World War II. With an enemy from the German Third Reich’s magi division, it has become a Holy Grail War hidden in history.
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