Category talk:Art from Pokémon Red and Blue
Second art set detail
This second art set's first known appearance is claimed to be in mid-March 1997, in the April issue of CoroCoro comic, a few months after the initial limited mail-in release of the Japanese Pokémon Blue Version. Both sets were illustrated by Ken Sugimori. This YouTube video tracks the history of the original watercolor art sets. It is a thorough review: https://youtu.be/F-lqvs-S280?t=721. However, page 15 of a Japanese Pokémon Blue game manual shows art of Red on a computer listed in this second set. For a conclusive first-appearance, a manual which can be traced to the first release of Japanese Blue should be reviewed.
The box art on the Japanese Pokémon Blue is not part of either set. The back of the Pokémon Blue manual uses Squirtle art from the first art set.
original message by @Doublefelix921 here