MissingNo., The Complete Profile of Pokemon's Most Famous Mistake
MissingNo., I love it! And I know you have heard of it too, because everybody has. It is the most famous glitch in video game history, the thing that made a generation of kids surf up and down the coast of Cinnabar Island, and the reason so many of us had 128 Master Balls we did not earn. But here is a question I never see anyone ask. How strong is it, actually?
Well since you are asking so politely, I will tell you. Its Defense stat is zero. Not low. Zero. Let me give this legend the full physical it never gets, because the answers are stranger than the item trick.
What is MissingNo., really?
Every Pokemon in Generation 1 is stored as a number, and MissingNo. is what the game shows you when it reads a number with no Pokemon attached (I covered how this works in the glitch Pokemon ranking, which MissingNo. famously did not win, and by the end of this page you will see why). Its Pokedex number is 000, and its name literally means Missing Number. The developers even gave it a placeholder identity: a dual Bird/Normal type, using a Bird type that exists in the game's code but was never given to any real Pokemon. So MissingNo. is not some demon hiding in the game. It is the game politely saying "file not found" in the shape of a backward L.
The stats nobody checks
Base stats (Red/Blue, documented)
That 136 Attack is genuinely impressive. Snorlax, the best physical attacker most Gen 1 players ever used, sits at 110. So MissingNo. out-punches Snorlax, which is a sentence I enjoyed typing. The problem is everything else. 33 HP, 29 Speed, a Special of 6, and that perfect zero in Defense, which means every physical hit that touches it is a personal tragedy. The total comes to 204, and for reference, the winner of my ranking has a total of 715. MissingNo. is the most famous glitch Pokemon and one of the weakest ones you can actually catch. Fame and stats are different statistics.
And the moveset. I need you to appreciate that this Pokemon knows Water Gun twice. Two separate move slots, both Water Gun. Somewhere in the garbage data the game decided one Water Gun was not enough, and honestly, who am I to argue with the memory of a Game Boy.
Why do you have 39 of them?
MissingNo. is not one glitch Pokemon, it is a family. There are 36 index numbers that all show up as the classic backward-L form, plus three special forms that borrow real sprites: the Kabutops Fossil, the Aerodactyl Fossil, and the Ghost from Lavender Town. That makes 39 in total. I pulled the full slot map from my own cartridge ROM to check, and there they are, all 39 index numbers pointing at Pokedex entry 000:
One honest note, because this series does not cut corners: MissingNo.'s stats do not live in the normal base stats table where every real Pokemon keeps theirs. When the game builds a dex-000 Pokemon it reads from somewhere else entirely, which is exactly the kind of behavior that earned it the profile you are reading. The stat figures above are the community-documented values, and they match what you see in an actual encounter.
The item trick, explained properly
Now the famous part, and the mechanism is prettier than the myth. The game keeps one bit of memory to remember whether you have "seen" each Pokemon for your Pokedex. MissingNo.'s "seen" flag happens to live on the same bit as part of the quantity number of the sixth item slot in your bag. So the moment MissingNo. appears on screen, the game flips that bit to record the sighting, and your sixth item's count jumps by 128. The duplication is not a reward and not a secret feature. It is two pieces of data accidentally sharing a bed. Put your Rare Candies in slot six before you go, that part of the legend is real.
So is it dangerous or not?
Here is the surprisingly reasonable answer: mostly not. MissingNo. does not freeze Red or Blue. You can encounter it, catch it, and even battle with it. If you keep one in your party your screen sprites can get scrambled, and the documented fix is charmingly simple, you just view the stat screen of any normal Pokemon and the scrambling clears up.
The physical, summarized
MissingNo. is a filing error with a fanbase, and it earned it. It out-punches Snorlax and loses to a stiff breeze. It knows Water Gun with twice the commitment of any other Pokemon. It comes in 39 flavors including two fossils and a ghost. It gives you 128 of whatever you love most, and all it asks in return is your Hall of Fame. There are stronger glitch Pokemon, several of them, ranked here, but there will never be a more famous one.
If you go visit it, do two things for me. Put something good in bag slot six, and give the old landmark a respectful nod. It has been holding the door open to the glitch world since 1996.
Sources: mechanism and documented figures from Bulbapedia's MissingNo. research; the 39-slot index map extracted from my own Pokemon Blue ROM. More specimens live in The Glitchhouse.
Go deeper: MissingNo's decoded profile in the Glitchhouse · battle it in the engine.