Pokémon Blue Version/Changelog

The following covers changes made to Pokémon Blue Version and Pokémon Red Version from Pocket Monsters: Blue.


 * The Pocket Monsters brand was changed to Pokémon.
 * Many sprites are censored, such as Jynx.
 * The Town Map border was removed, and the text box was widened for localization reasons.
 * Pokémon names can now allow more than five characters for localization reasons.
 * Pokémon PC storage system was changed from 8 boxes that can hold 30 Pokémon each to 12 boxes that can hold 20 Pokémon each.
 * Blizzard's chance of freezing an opponent reduced to 10.2% from 30.1%.
 * The moves Absorb, Mega Drain, Leech Life and Dream Eater will succeed if the opponent has a substitute out, but will fail in Pocket Monsters: Green, Pocket Monsters: Red, Pocket Monsters: Blue and Pocket Monsters: Pikachu. Despite being a bug, it continued to be present in all Generation II video games released worldwide before being fixed permenantly in Generation III.
 * A glitch where withdrawing the potion at the beginning of the game allows you access to the Pokémon menu has been fixed, and now warns you that you cannot use the item as you don't have any Pokémon.
 * The man blocking the player's initial progress in Viridian City in the Japanese releases was because he was drunk. In the international releases, this was changed to him not having had his morning coffee.
 * The move Swift is supposed to never miss against an opponent, even if the opposing Pokémon is in the middle of a move like Dig or Fly, where they would normally be invulnerable. However, due to a bug in the Japanese releases only, Swift is only an unmissable move if the enemy Pokémon has a substitute out. In all other cases, Swift acts as a normal move, which also means that it's affected by accuracy modifiers (such as Double Team and Sand-Attack) and also by the the 1-in-256 base chance of missing like any other move in Generation I.
 * In Pocket Monsters: Green, Pocket Monsters: Red, Pocket Monsters: Blue and Pocket Monsters: Pikachu, plus the International releases of Pokémon Yellow Version: Special Pikachu Edition), if the player already has two Pokémon species registered as caught (for example, by evolving their starter Pokémon) before returning to Professor Oak to deliver Oak's Parcel, the game acts as if the player has already obtained the Pokédex, even though they haven't; thus it becomes impossible to progress through the game, because the old man in Viridian City blocking the player's progress will only move after the player has actually obtained the Pokédex.