This hack does what's shown in the screenshot:

• In battle, a Pokéball icon is shown next to the enemy's status if that species is registered as Caught in the Pokédex, like in all later Pokémon games.
• In battle, moves' (approximate) accuracy and power are shown.
• In battle, both level and SLP/BRN/PAR/FRZ are shown (if applicable).
• Some things are moved around on the screen a little to accommodate these changes.

Bugs/Features:

• The Pokéball icon is shown next to a caught species even in trainer battles. (Which I like, because sometimes you wonder if you have that one, even though you can't catch it right now.)
• Accuracy is stored as n/255 in the game; this hack displays a percentage, rounded down. So e.g. Horn Drill shows an accuracy of 29% rather than 30%.
• Power is displayed even for moves that don't use it (non-damaging moves, OHKO moves, etc); the values might be a little strange in those cases.

This patch should work on Red (English version). Possibly it will work on Blue, too. Probably not on Yellow. Try it though and see if any interesting glitches result.

Download IPS patch

Also, this version makes the player walk faster (including when moving on those stupid spin tiles). As a side effect it disables the spin tiles' animation, but oh well. (The player character still spins, though!)

Download fast-walking version

If you want only the walk faster effect, it can be done with a pair of Game Genie codes:
C9F-E9B-081: Faster movement on spinning tiles. (Also disables spin tiles' animation)
005-D1F-C42: Faster walking and surfing.

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