2nd Gen Mysterious grass in Pokemon Yellow

[myrrhman]

Using a cheating device, you can get there, and if memory serves me right, if you hold down the B button, it prevents the game from freezing. You are able to encounter wild Pokemon in the grass, and they are not the normal Pokemon that you encounter. But, if you do not hold the B button, your game freezes.

 

[Heart's Soul]

Using a cheating device, you can get there, and if memory serves me right, if you hold down the B button, it prevents the game from freezing. You are able to encounter wild Pokemon in the grass, and they are not the normal Pokemon that you encounter. But, if you do not hold the B button, your game freezes.

I held down every button combination I could in that grass, it freezed with a 99.9997% chance. The other .0003% was just that one random time I went there, and the game messed up, but didn't freeze! Freezed the next step over.

 

[Niprop]

There were rumors that "Pallet Fields" (as the grass on each side of Route 1 and Pallet Town was called) held a variety of things, including high-powered or rare Pokemon such as the starters or Mewtwo, and other times PokeGods. There was even talk of a staircase that led to Johto.

Both aren't true, of course, but may be rooted in a Japanese Green version glitch in which traveling across the barrier can lead to a somewhat glitched-up hidden beta city.

That's odd, considering that the only known Beta City in R/G/B/Y is above the Indigo Plateau. The chances of warp panel to that place in specific to be generated by a glitch are exceedingly slim, in fact, I don't even know if said area is even accessible without crashing the game.

Also, what you seem to be describing sounds similar this glitch: https://bulbapedia.bulbagarden.net/wiki/Dokokashira_door_glitch

Anyways, going into those patches of grass normally will make your game crash, or in other cases, glitch. You shouldn't be able to find anything in the grass because no Pokémon are defined to appear in that specific area.

 

[Guest123_x1]

decorative grass

When I first started playing the games, I thought the patch contained rare Pokémon or something else exciting.

I tried accessing this strip of grass with a cheating device and it froze up the game.

Even if it were accessible without freezing up the game-it would probably contain the same Pokémon as on the accessible part of Route 1 (Pidgey and Rattata). It's only there for decoration.