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The Tsuchinoko (ツチノコ or 槌の子) meaning "hammerspawn", is a legendary snake-like cryptid from Japan. The name tsuchinoko is prevalent in Western Japan, including Kansai and Shikoku; the creature is known as bachi hebi (バチヘビ) in Northeastern Japan.
Tsuchinoko are described as being between 30 and 80 centimeters in length, similar in appearance to a snake, but with a central girth that is much wider than its head or tail, and as having fangs and venom similar to that of a viper.
The tsuchinoko appears in some games as a secret monster or rare creature; for example, Metal Gear Solid 3 or Castlevania: Aria of Sorrow.
Kirisame Marisa decided to take the tsuchinoko found in Strange and Bright Nature Deity home as a pet, though it's not certain if she still has it...
For the Youkai Watch character, see Tsuchinoko (Youkai Watch). For the Kemono Friends character, see Tsuchinoko (Kemono Friends)