It can be found in the Yellow Version by doing Method #3 of the Mew glitch using a Pokémon with a special stat of 197. Its Red and Blue equivalent is PkMn (C5). It is a hybrid of Golduck. Its data entry, weight and height are the same as Dragonair's. The only differences are the picture and the fact that its species appears as RAGON instead of DRAGON, not unlike .8 and ゥゥ].
This is a unique glitch Pokémon because of the fact that it has multiple front sprites when in the wild. All have the same chance of encounter, but once caught it will appear as the sprite seen in its Pokédex entry.
This glitch Pokémon article is part of Project GlitchDex, a Bulbapedia project that aims to write comprehensive articles on glitches in the Pokémon games.