Originally written on 2011 January.
Pokémon has been a fixture of many childhoods, and of all the Pokémon, seem few to captivate as much as Mew. He was popularized in the very first Pokémon movie, which featured a showdown between Mew and his clone, Mewtwo. He then later reprised his role as Mew in the eighth movie, Lucario and the Mystery of Mew.
Mew had a wide appeal for being both immensely cute and immensely powerful and for being a perfect personification of curiosity and humility. But after all of these encounters with Mew, one mysterious question remains: Is Mew a Ditto?
The General Theory and Basic Facts
Ditto is a lot less popular than Mew, but just as enigmatic. This Pokémon only has one ability — the ability to transform, or shapeshift, into pretty much anything else, with a few limitations. But of course, there is a key connection here, because there is one other (and only one) Pokémon who can transform… Mew.
The mutual ability to transform may be enough to seal the connection — if Ditto can transform into any Pokémon and if Mew can transform into any Pokémon, they already become interchangeable since they can both transform into each other. With this stunning realization, I had to check the internet.
Of course, I ended up not being the first person to come up with this theory. A search brought up this summary, which added additional facts beyond the Transform connection:
- In the Pokédex, Mew and Ditto both have the same stated weight of 8.8lbs.
- Both Mew and Ditto share the same colour scheme, a Pink when normal and Blue when shiny.
- Both Pokémon are genderless.
From this, the image comes to the conclusion that “Ditto is a failed Mew clone”.
Of course, if we want to be analytical and scientific, we cannot just stop here and assume the case is closed. A quick look at the complete list of Pokémon sorted by weight reveals that Ditto and Mew are not alone at 8.8lbs — they share that weight with Bellsprout, Shelder, Seedot, and Victini. Also, with 41 other Pokémon being genderless, Ditto and Mew may not be as related as they seem.
However, how many Pokémon are both genderless and weigh the same? Well, in order to find out, we’d have to run 1640 comparisons, so it looks like it’s time to outsource this to a computer. I made a program to grab the weights of all the genderless Pokémon and then sort by weight. I found the following matches.
- Azelf – Uxie – Rotom – Mesprit at 0.7lbs
- Ditto – Mew – Victini at 8.8lbs
- Celebi – Unown at 11lbs
- Magneton – Moltres at 132.3lbs
- Bronzong – Suicune at 412.3lbs
- Goruugu – Reshiram at 727.5lbs
Clearly, having the same weight and genderless attribute does not make two Pokémon the same at all. It is entirely possible that the shared weight and gender are a simple coincidence. (I’ll get to an analysis of the shared sprites later, in a different section.
Despite having a decent amount in common, Mew and Ditto have a decent amount not in common. For example, they do not share the same height, body type, species, abilities, experience at level 100, Pokéball catch rate, breeding type, or base exp.
A Comparison of Transforms
Now let’s look deeper at their shared transform connection. Sure they both transform — but do they both transform the same? In all of the electronic Pokémon games Mew and Ditto use the same Transform move with no differences. The only difference is Mew can learn additional moves (in fact, all moves) other than transform, while Ditto may only use transform.
In the Trading Card Game, however, multiple Ditto and Mew cards use various different transform mechanics. Ditto can copy an opposing Pokémon’s stats directly, be replaced by (transform into) a new Pokémon from your deck, be replaced by (transform into) a different Ditto card, copy an opposing attack, or copy all opposing attacks. Only one ditto card has no transformation abilities.
Mew, on the other hand, has many cards that don’t transform at all. However, of the Mew cards that do transform, Mew can copy the opponent’s type, copy an opposing attack, use attacks of searched and removed Pokémon, or copy all attacks. Mew does not have quite the same range of transformation as Ditto, but does share a few transformation mechanics.
Transformation in the Anime
Lastly, we turn to the anime series for Pokémon to compare the way in which Ditto and Mew transform.
In the Anime, Mew does not regularly transform until Lucario and the Mystery of Mew, in which he transforms a lot. Furthermore, whenever Mew transforms, he does so effortlessly, taking on exact duplications of any Pokémon Mew can think of.
Ditto in the Anime is far more limited. Ditto transforms into non-Pokémon objects, a feat that Mew may or may not be capable of, but has occasional frustrations — one Ditto was unable to change its face and another ditto was unable to change its size. Ditto has also been described in Pokédex entries as only being able to transform into something it can see, though I’m unsure if this is just yet another occasional limitation.
Overall, there seems very little difference between the way the two transform, and both are the only Pokémon capable of the move. The transform connection remains a compelling argument.
An Analysis of Sprites
Another argument for Mew-Ditto similarity is a comparison of their sprites in the electronic games. Specifically, their sprites for both normal and shiny are the same colour. Overlaying images taken from Bulbapedia (under their license), we find:
From the image, you can tell it’s a pretty good match. Sure, they’re not identical — Ditto skews more purple than Mew, whereas Mew skews more pink — but on the whole the sprites are very similar. The only anomaly is Pokémon Yellow, in which Mew skews Yellow while Ditto skews green.
Sprite Matching in the Anime
However, in the Anime the sprites don’t match as well — Ditto is seen as purple, whereas Mew is portrayed as white.
But again, we’re forced to ask ourselves — how much does sprite matching really matter? Could a palette match just be a coincidence? Initial data points to yes. Consider this match between Kakuna and Sandshrew — two completely unrelated Pokémon:
There is a very limited match in Red, Blue, Yellow, Gold, Silver and Crystal; but afterward there is a sprite match in every game. However, the sprite match isn’t the only similarity…
Coincidence of Sprites and Physical Characteristics?
How many Pokémon are both genderless, have the same weight, and have matching sprites? Let’s look back at our list:
- Azelf – Uxie – Mesprit – Rotom :: (Azelf – Uxie – Mesprit match, Rotom does not)
- Ditto – Mew – Victini :: (Ditto – Mew match, Victini does not)
- Celebi – Unown :: No sprite match
- Magneton – Moltres :: No sprite match
- Bronzong – Suicune :: No sprite match
- Goruugu – Reshiram :: No sprite match
Lake Trio Comparison
There does seem to be one other pretty good sprite match among the lake trio: Azelf, Uxie, and Mesprit.
What should we make of that? Are the Lake Trio all the same Pokémon too? I think there’s enough of a difference between the three sprites (their respective hats) to show that the Pokémon are intrinsically related, but not identical. Of all Pokémon that are not evolutions of each other, the match of sprites between Ditto and Mew is still a stronger match than any other two Pokémon.
From this evidence, it seems there is as much implied connection between Ditto and Mew as there is between the Lake Trio, or more. Since the only other Pokémon to match in gender, weight, and sprite are intended to be connected, this gives us evidence that Ditto and Mew were also intended to be connected at least in the electronic games, but possibly not in the Anime.
Two Uncompelling Arguments
The Pokemon Mansion
An additional connection between Mew and Ditto that is brought up involves their placements within Pokémon Yellow. Specifically, Ditto is one of the Pokémon that can be found in the wild in The Pokémon Mansion, where Mew was cloned.
However, I really don’t find this line of evidence at all convincing, given that Ditto is not found in the Pokémon Mansion in either Red or Blue, but instead found in several other places. Secondly, within Yellow, Ditto can still be found in the Cerulean Cave. Lastly, other wild Pokémon besides Ditto can also be found in the Mansion in all games.
Shared Connection in Glitches
A second argument for the connection that also does not hold weight is the involvement of Ditto and Mew in many glitches. Most notably, Ditto is required to catch a wild Mew via one method of the Mew Glitch. However, this ignores the fact that there is nothing really notable or ostensibly intentional about Ditto’s role in this method, and ignores the fact that there are two other methods to invoke the glitch that do not involve Ditto at all.
Given all of this data, is there any evidence to indicate that Mew and Ditto are the same Pokémon, or that there is any intended connection between the two? Or rather, is it indeed all simply a coincidence?
It’s hard to really tell.
Ditto was obviously pre-planned as an intentional Pokémon for the game, however Mew was a later addition, added in to the original Pokémon games as a secret.
Given that, I think that the commonalities of weight, sprites, gender, and signature move of transform is enough to suggest that Mew was an intentional copy of Ditto. If I were to suggest a history, Mew was added in at the last minute by the game developer by duplicating the data for Ditto and then adding to it, with the sprites minimally changed.
Continuing with the “Mew is a copy of Ditto’s game data” theory, one website suggest that:
And for a bit of botched game programming being used in the argument, if you catch a Mew that’s used Transform in Gen 1 and 2 [Red, Blue, Yellow, Gold, Silver, and Crystal], then you’ll end up with a Ditto instead.
…Though I an unable to test this or find any confirmation.