1636 Pokemon Fire Red - U-- Squirrels Link

Squirrels do not exist natively in Fire Red . The closest:

Verdict: “1636” is likely a from a ROM set, possibly No-Intro naming: 1636 - Pokemon Fire Red (U)(Squirrels).gba — where “1636” is a serial number from a scene release group, and “Squirrels” is an internal folder or tag. 1636 Pokemon Fire Red - U-- Squirrels

At the Cerulean City bridge, just before the rival battle, the game triggers an unskippable cutscene. The screen fades to black. Then, 47 squirrel sprites fill the screen in a grid formation. Each one plays a different chitter sound simultaneously. After 10 seconds, the game resumes normally—except your starter’s name is now permanently “NUTS.” Squirrels do not exist natively in Fire Red