The Glitch Pokémon That Freed Trainers From Their Money Worries – The Story Behind The World-Famous MissingNo Glitch

Anyone who has ever played a Pokémon game is likely familiar with one of the most famous glitches in gaming history. Here, we’ll explain what MissingNo is all about and how the glitch works.

Let’s take a mental journey back to a time when the internet wasn’t just "uncharted territory" for us – it was an unreachable, alien planet in a distant galaxy. A time of playground gaming rumors, where a cousin’s best friend from another school had supposedly seen something absolutely crazy in Pokémon, or a third-degree uncle worked at Nintendo and could confirm even the wildest theories our classmates could dream up.

During this very time, Pokémon Red and Blue fueled our imaginations and kept the rumor mill churning.

MissingNo – The Poké-Glitch

From simple tales like holding the B button to increase the chances of catching a wild Pokémon, to somewhat believable theories about the S.S. Anne making a return, and even absurd rumors about evolutions or fusions of Charizard, Venusaur, and Blastoise – fans’ imaginations knew no bounds.

During this very time, players also encountered MissingNo – a glitch that actually existed in the games, further blurring the lines between rumors and reality...

The Unique Master Ball – Not So Unique After All

Since very few people had a working internet connection at the time, no one could verify exactly what MissingNo was. But whether it was a secret special Pokémon, a Poké-god (or devil), a virus, or just a glitch, what mattered most at first was how incredibly useful this strange phenomenon was for players.

At first, it wasn’t just MissingNo itself that players encountered, but also various other Pokémon that were either unusually found in specific locations or had levels far exceeding the 100 cap – though these pocket monsters were highly unstable. Some had no moves, others would suddenly change form in the middle of a game, or their levels would unexpectedly drop from 128 to 0. So, while they were fascinating, they didn’t really offer any tangible advantage in the game.

Instead, the whole thing was interesting and sought after for a different reason.

Anyone who encountered MissingNo would soon notice, upon checking their bag, that certain items had multiplied. Max Revives, Rare Candies, or even the unique Master Ball could suddenly be used hundreds of times.

In addition to the simple fact that many of these items were incredibly useful on their own, they could also indirectly help players obtain highly sought-after, rare Pokémon. For example, if you wanted to own a Porygon, you had to earn it at the arcade – or exchange your hard-earned Poké Dollars for coins. Thanks to MissingNo, this was no longer an issue, as items could be endlessly duplicated and then sold, making it easy to buy large quantities of game coins.

To this day, MissingNo remains one of the most famous glitches in gaming history.

Activating The Glitch

If you want to experience the glitch Pokémon and its abilities for yourself, you’ll need to follow a specific sequence of steps – steps that have likely been burned into the memory of most players from that time:

1. First, head to Viridian City and let the old man on the outskirts show you how to catch Pokémon.
2. Then, immediately use Fly or Teleport to reach Cinnabar Island.
3. Head to the island's eastern coast, use Surf, and swim up and down the coastline where the land and water meet.
4. If you’ve followed these steps correctly, you’ll encounter "corrupted" Pokémon – and eventually, MissingNo itself.
5. After the encounter, the item that was in the sixth slot of your bag will be multiplied.

What Exactly Is MissingNo?

Today, thanks to widespread internet access, we know that MissingNo is neither a virus, a Poké-devil, nor a creature from a creepypasta, but simply a glitch. And as the name suggests, it's one caused by missing data.

To put it simply:

MissingNo, or Missing Number, refers to an "emergency" in the game.

Since all 151 Pokémon of the first generation are stored in the game’s memory, but memory slots are only available in powers of 2 (1, 2, 4, 16, 128, 256, etc.), even with the smallest unit that can hold all 151 Pokémon – 256 slots – there are still 105 extra slots.

Due to certain errors, the game can be tricked into accessing these unused memory slots. Since no Pokémon or their number is stored there, the result is the appearance of "MissingNo".

The Origin of the Glitch

Certain actions can cause the game to attempt to use these memory slots, which leads to the MissingNo glitch.

At the beginning of the game, you give your character a name, which is used by various NPCs to address you. This name has a fixed spot in your game's memory and stays there consistently – except for one case: when you let the old man in Viridian City show you how to catch Pokémon, his name will appear on the battle screen. At that point, the game replaces your name with "Old Man" in that memory slot.

To make sure you get your name back afterwards, it is temporarily moved to a different location – specifically, the section that controls which Pokémon can appear in the tall grass at your current location. Since you're in a city and there’s no tall grass here, this slot is currently unused and free.

After the old man's demonstration, the spot where his name was stored is now overwritten with your own name. However, the section that controls Pokémon encounters in the tall grass remains unchanged. Even traveling to Cinnabar Island doesn't alter this, as there is no tall grass there either.

However, the coastline of the island is still classified as tall grass, which ultimately means that the game attempts to access the memory slot where Pokémon encounters are stored. But instead of finding a Pokémon, it only finds the player’s name.

This error causes MissingNo to appear. However, while every other Pokémon has two bits for "Seen" and "Caught," each set to either 0 ("no") or 1 ("yes"), the bits or information for the unwanted exception, MissingNo, are stored elsewhere, specifically in the sixth slot of your item bag. Since the game tries to display a binary value here, it ends up showing a 128 instead of the expected item count.

Another fun fact learned! Did you encounter MissingNo back in the day? If so, what did you think it was? A glitch, a virus, a creature from a creepypasta? Tell us in the comments!