Changes in the behaviour of Poké Flute (with a sleeping party) outside of battle (Generations I-III)
32Notes: In Generation I, using the Poké Flute outside of battle with a sleeping Pokémon in the party doesn't actually do anything, returning the usual "Now, that's a catchy tune!" (Japanese: うーん！ すばらしい ねいろだ！). In the Japanese versions of Yellow, this was curiously changed to "ポケモンのふえだ！ ねむったポケモンを おこせるかも...", also appearing if none of the Pokémon are asleep.
As revealed from osrc.zip in the 2018-2020 Nintendo data leaks, a preliminary translation for the exclusive Japanese Yellow behaviour was meant to be "Sleeping Pokemon don't like this!" (even though literally it is like "It's a Poké Flute! I wonder if you can awaken sleeping Pokémon with this...", but this translation never made it into the final localisations, with the ordinary "Now that's a catchy tune!" still appearing. Nintendo of America brought it up as a bug for Pokémon Yellow, but it seems in the end you still couldn't awaken party Pokémon outside of battle with the Poké Flute in the localisations and the message was left as "Now, that's a catchy tune!".
(The exact report is as such and curiously the report also got the Japanese name of Poké Flute wrong (ポケフルート rather than ポケモンのふえ))
"
＃８：ポケフルートは戦いの外の眠りポケモンには通用しない。戦い
の外でそれを使用しようとすると、テキストメッセージ「眠っているポケモン
はこれが好きじゃない！(Sleeping Pokemon don't like this!)」が出る。
"
When Pokémon Gold and Silver were in development, item 0x38 (now a Teru-Sama) had the behaviour of a Poké Flute with functionality for waking up Pokémon outside of battle, playing the music and displaying "All sleeping POKéMON woke up." (Japanese: すべての ポケモンが めを さました!) (and ignoring the "Played the POKé FLUTE. Now, that's a catchy tune!" message if any were asleep). This can be restored using a cheat code to bring back the Use option/'fix' the attributes of that Teru-Sama in the final game. The final game's Poké Flute only works from the Pokégear radio, but seemingly doesn't actually wake up any party Pokémon.
With the release of Pokémon FireRed and LeafGreen, the Poké Flute wakes up sleeping party Pokémon outside of battle and displays a different message "The POKé FLUTE awakened sleeping POKéMON." (Japanese: ふえのねを きいた ポケモンは めを さました) (note also the Japanese text uses the は particle instead of が and is missing a full stop or exclamation mark at the end).