Keystone (クサビ石), also known as Blackstone (ブラックストーン) to Shinkansen Ultra Evolution Institute, is a kind of huge crystal formations buried underground in multiple locations throughout japan. It first appears in Episode 02 of Shinkansen Henkei Robo Shinkalion Z.
Known locations of Keystones
- Yokokawa, Gunma Prefecture (Episode 02, destroyed by the Dark Shinkalion in Episode 23)
- Morioka, Iwate Prefecture (Episode 04, destroyed by Gorgon All Along)
- Kagami-ike, Nagano Prefecture (Episode 06, destroyed by Definitely Ungaikyo)
- Mt. Hōman, Fukuoka Prefecture (Episode 10, destroyed by Deabols in Episode 29)
- Inuyama, Aichi Prefecture (Episode 12, intact)
- Sekigahara, Gifu Prefecture (Episode 13, destroyed by Valtom in Episode 27)
- Mt. Hiei, Kyoto Prefecture (Episode 17, intact)
- Maibara, Shiga Prefecture (Episode 22, unknown status)
- Ueno, Tokyo (Episode 22, destroyed off-screen)
- Ōboke, Tokushima Prefecture (Episode 25, intact)
- Tōno, Iwate Prefecture (Episode 26, intact)
- Cape Tappi, Aomori Prefecture (Episode 28, destroyed by Sougyoku)
