Old Man Glitch Decoder

Pokémon Red / Blue / Yellow — trainer-name encounter preview

Type up to 7 characters (letters, digits, or the symbols below each box). The 1st character has no effect — the glitch never reads it. Boxes and results outlined in orange (⚠) are documented to freeze the real game.

How this works

In Gen 1, walking away from the Old Man in Viridian City right after he "shows you how to catch a Pokémon" can trigger a glitch encounter built from bytes of your trainer's name. Positions 3, 5, and 7 of the name are read as a Pokémon species byte, and positions 2, 4, and 6 are read as that encounter's level byte — three separate (species, level) pairs.

The species comes from the game's internal index table: every nameable character (A–Z, a–z, digits, and a handful of symbols) has a raw byte value from 128–255, and that byte doubles as a species ID in the Pokémon index.

The "level" isn't computed at all — it's the same raw byte value, printed as-is. That's why these encounters always show absurd levels (128–255) instead of the normal 1–100: the game is misreading a name-entry character as if it were a level.