Its long tail serves as a ground to protect itself from its own high-voltage power.
This card was included in the Base Set, first released in the Japanese Expansion Pack. It was reprinted in the Base Set 2 expansion. It was reprinted with a Non Holofoil print in the Japanese Pokémon Web. Some copies of this card, estimated by Wizards of the Coast to be around eight, were stamped with a Prerelease symbol. Card sheets were eight by eleven so there is said to be eight to ten copies in existence. These cards came about during the manufacture of the prerelease JungleClefable, as a result of a few Base Set Raichu cards appearing on the sheet of Clefable cards being made for prerelease. Wizards denied the existence of prerelease Raichu for years, until one of their staff released an image of the card in 2006. Due to the card's excessive rarity, prerelease Raichu is said by some to be the "Holy Grail of Pokémon".