2x2 block encounter glitches
0x1500 control code arbitrary code execution (Crystal) | Cart-swap arbitrary code execution | Generation I custom map script pointer | Generation I invalid meta-map scripts | Generation I item ("8F", "ws m", "-g m", "5かい", "てへ" etc.) | Generation I move ("-", "TM42") | Generation I Trainer escape glitch text boxes | Generation II bad clone | Generation II Burned Tower Silver | Japanese Crystal Pokémon Communication Center SRAM glitches | Coin Case glitch | Generation II glitch Pokédex sortings | Pikachu off-screen glitch ACE | OAM DMA hijacking | Pikachu glitch emote | Generation III glitch Pokémon summary | Generation III glitch move animation) | Remote code execution | TM/HMs outside of the TM/HM pocket | ZZAZZ glitch Trainer FC
No further extensions
Cloning | Item duplication glitch (Generation I) | Pokémon merge glitch ("Q Glitch", Generation I) | Time Capsule exploit | Bug-Catching Contest data copy glitch (Generation II, Japan only) | Berry glitch | Battle Tower Lati@s glitch (Generation III) | (Mimic) Transform Rage glitch (Generation IV)
Transform held item glitch (Generation IV, Japan only) | Mimic glitch (Generation IV, Japan only)
99 item stack glitch | LOL glitch | Rival LOL glitch | Instant LOL glitch | RAM LOL glitch | Out of bounds LOL glitch | blockoobLG | Instant encounter infinite chain glitch | LGFly | Super Glitch (Generation I) | Party remaining HP glitch | Super Glitch (Generation III) | Text pointer manipulation mart buffer overflow glitch | CoolTrainer♀-type move | Double distort CoolTrainer♀ corruption | Yami Shop glitch | Party Pokémon box data shift glitch | Unterminated name glitch item instant encounter (Japanese Red/Green)
Item stack duplication glitch (Generation I)
Generation I expanded items pack (Glitch Rocket HQ maps, Map FE (English and non-English European Yellow) | Map script pointer manipulation (arbitrary code execution | Map script pointer item ball manipulation) | Text pointer manipulation (arbitrary code execution | Item ball manipulation | Mart buffer overflow) | Trainerless instant encounter glitch
Bad clone glitch (Generation II)
????? party overloading (Type 0xD0 move glitch | ????? map corruption | Celebi trick | Celebi Egg trick | Shiny Celebi trick | Glitch move map corruption | Overloaded party map corruption | Glitch Unown (Glitch Unown map corruption) | Duplicate key items glitch (Infinite items and item creation, Expanded Balls pocket (Wrong pocket TM/HMs, Glitch Pokédex categories))
Closed menu Select glitches (Japanese Red/Green)
Dokokashira door glitch (International) | Fossil conversion glitch (international) | Second type glitch | Skip to Level 100 glitch | Trainer mutation glitch | Walk through walls (International) | Lift glitch | Badge describer glitch
Pomeg glitch (Generation III)
Pomeg data corruption glitch ("Glitzer Popping") | Charm glitch
Voiding (Generation IV)
Broken escalator glitch (Japan only) | Elite Four door glitch (Japan only)
2x2 block encounter glitches (Generation I)
Left-facing shore tile glitch (in-game trade shore encounter trick, Old man trick, Trade link up shore encounter trick, Fight Safari Zone Pokémon trick) | Viridian Forest no encounter grass tiles glitch
Safari Zone exit glitch | RAM manipulation | Out of bounds Glitch City (Generation II) | Slowpoke Well out of bounds corruption (French Gold/Silver/Crystal)
Large storage box byte shift glitch
Storage box remaining HP glitch | Generation I max stat trick
SRAM glitches
Generation I save corruption | 255 Pokémon glitch | Expanded party encounter table manipulation (Generation I) | Send party Pokémon to a new game (Generation I) | Generation II save corruption | Mailbox glitches | Mystery Gift item corruption | Trainer House glitches
Death-warp | Ditto trick | Experience underflow glitch | Mew trick | Text box ID matching | Meta-map script activation
Ledge method | Museum guy method | Rival's effect | Select glitch method (International Select glitch method), Brock Through Walls
Grass/rock Surfing glitch (Spanish/Italian only) (adaptions: Submerge glitch (international)) | 8 8 (0x7C) grass/rock surfing glitch (English Red/Blue))
The 2x2 block encounter glitches are a group of glitches in Pokémon Red and Blue which were fixed in Pokémon Yellow.
These glitches occur when the game checks an encounter for a 2x2 tile, such as the left-facing shore tiles on Sea Route 20, or the grass tiles with a star on their bottom-right corner in Viridian Forest.
In English versions, the left side of the tile controls the encounter list source (grass, water or none) and the right side of the tile controls the encounter rate source (grass, water or no encounters). Due to 'shore' (left side of the tile) counting as grass encounters and 'water' (right side of the tile) counting as water list, left-facing shore tiles can bring up unintended grass encounters. Similarly, due to 'grass' (left side of the tile) counting as grass encounters and 'star grass' (right side of the tile) counting as no encounters encounters can be avoided in Viridian Forest by walking on the star grass tiles.
- Viridian Forest no encounter grass tiles glitch — Encounters are disabled for the grass tiles with a star-shaped grass sub-tile on their bottom right corner.
- Left-facing shore tile glitch (in-game trade shore encounter trick, Old man trick, trade link up shore encounter trick, Fight Safari Zone Pokémon trick) — Encounter unintended grass list Pokémon or unintended Pokémon from leftover data stored in
Similar glitches
- Grass/rock Surfing glitch (Spanish, Italian versions only) — These glitches fixed the left-facing shore tile glitch but seem to have allowed water encounters with a grass rate encounter rate if the player is Surfing on grass or a rock via the Surf down glitch. The water list can be manipulated by fighting a Trainer beforehand.
- English grass/rock Surfing glitch — The water encounter rate (manipulated after encountering a Trainer) can be forced to remain as a non-00 value through a trick that involves use of the glitch items 9F (hex:5E) and 8 8 (hex:7C).