Please note that this glitch only exists in the Japanese versions of the game, or is otherwise a glitch from a Pokémon game which was only released in Japan. |
The Yellow Scarf glitch occurs only in the Japanese versions of Pokémon Ruby and Sapphire.
If a Pokémon has a Smartness condition of at least 200, it will be eligible to receive both the Green Scarf and Yellow Scarf even if the Pokémon does not have a Toughness condition of 200 (the intended requirement for the Yellow Scarf).