End of log.

Its stats were impossible. Level 0. Type: Fire/Normal. Ability: Glitch Husk — immune to all attacks except those that miss intentionally. And its only move, Ember Cache, did not deal damage. Instead, it replaced one item in your bag with a “Burnt Acorn.” The acorn, when used, simply displayed the text: “The acorn remembers a colder autumn.”

For context, there are no squirrels in Kanto. Not one. The region boasts electric mice, beavers, psychic foxes, and even living piles of sludge, but the humble squirrel— Sciurus vulgaris —is conspicuously absent. This is a botanical mystery, as Kanto is filled with oak and chestnut trees. Yet, in the 1636th line of the Pokémon species database, a ghost of a creature stirs.

Let me rewind to the historical parallel. The year is 1636 CE in the human calendar. In our world, that year marks the height of the Little Ice Age, the founding of Harvard College, and the beginning of the Pequot War in New England. But in the lore of Pokémon FireRed , 1636 is the year a cartographer named Ezekiel “Red” Maple, an ancestor of Professor Oak, sailed from the port of Vermilion City to explore the uncharted “Sinnoh Tangle.” His ship, The S.S. Anne , was lost at sea for six weeks. When he returned, he was clutching a small, burnt diary. The diary contained a single sketch: a rodent with a curled, fiery tail, storing nuts in a tree hollow. Below the sketch, written in faded ink, was the word “Risukooru” — an archaic transliteration of “squirrel.”

It began not with a bang, but with a rustle. In the autumn of 2004, while datamining the newly released Pokémon FireRed Version , I stumbled upon a hexadecimal sequence that should not have existed. The address was 0x1636. Within the game’s code, nestled between the cry data for Rattata and the sprite pointers for Spearow, lay a set of 12 unused bytes. When forced to compile, they generated a creature the fandom would later call the “FireRed Squirrel.”

The truth, I believe, is more melancholic. In the final, stable build of FireRed , the squirrel was erased. Its cry (a mix of a chirp and a crackle) was reassigned to the move “Sweet Scent.” Its sprite data was overwritten by a placeholder tree tile. But the 0x1636 index remained, a digital fossil. It’s what programmers call a “ghost in the machine”—a remnant of an idea that was too strange for the final product: a squirrel that survived a fire in 1636, only to be deleted in 2004.