In Metal Gear Solid 3: Snake Eater, the Tsuchinoko is an invisible snake that is undetectable by Radar and Thermal Goggles. Capturing and keeping it until the end of the game unlocks a special face camo that gives the player unlimited ammo on their next play-through.

The Tsuchinoko (ツチノコ) 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 in Northeastern Japan.