Pokemon Yellow runs on the original DMG Game Boy. But so do over a hundred other GBC games. These games have special GBC functionality, but are backwards-compatible with the GB. These GBC games were released on black cartridges. The question is: If Pokemon Yellow carts weren't yellow, would they be grey, or would they be black?

Here are all the reasons I've seen for whether the version of Pokemon Yellow should be considered an original Game Boy game or a Game Boy Color game. If you know of anything wrong/missing from this list, let me know. First, we'll start with…

Stuff that doesn't matter but gets mentioned sometimes

---

The Japanese version is grey
The Japanese versions of all 1st-gen pokemon games were on grey cartridges, while the international versions were released in special red, blue, and yellow cartridges. The Japanese version of Pokemon Yellow differs from the international versions, and is unquestionably an Original Game Boy release, with no forced color palette (see below) or any in-game Game Boy Color enhancements. There are many other games which were released as GB games in one region and GBC games in another.

Product code
Pokemon Yellow's product code is DMG-APSE-XXX. GB games and backwards-compatible GBC games followed the same product code convention, starting with DMG. Only clear-plastic GBC games started to use CGB product codes.

Different platform than Red/Blue?
Pokemon games are released in pairs; early generations also included a third version released after the first pair. Pokemon Yellow would not be the only "third version" game released on the same OR different platform than its original pair, so there's no info to be gained by looking here.

Release date
Pokemon Yellow was released in the US and Australia in late 1999 and Europe in 2000. A few dozen GBC titles were already released by then. It had been several months since the last Game Boy release, and no Game Boy releases came after this. If you looked only at this data and nothing else, it would be easy to guess that Yellow is a GBC title, but it doesn't actually mean anything.

Such-and-such website lists it as X
Hopefully we all know that it doesn't matter what a website says, the actual nature of the game is not affected/determined by common websites or popular opinion.
 

---

Alright, on to…
Stuff that maybe does matter

---

The box says GAME BOY on the front
https://i.imgur.com/kwW23ez.jpg...
Probably the most common argument for being a GB game is the box, which shows GAME BOY on the left side, not GAME BOY COLOR. No black GBC game does this, although some of their manuals do.

The box says Game Boy Color on the back
https://gamefaqs.akamaized.net/bo...
Like every dual-compatible black cart GBC game, the back of the Pokemon Yellow box shows two icons at the top: Compatible with Game Boy, and Compatible with Game Boy Color. No grey-cart Game boy game shows this, including games released after the GBC.

Forced color palette
https://i.imgur.com/HupBY.png...
https://krikzz.com/forum/index.ph...
When booting an original GB game on a GBC or GBA, a variety of color palettes can be selected by inputting certain button combinations at startup. This can only be done on games that do not have a built-in color palette. (The default palette on some games may be enhanced in a game-specific way, using data that is hard-coded into the GBC itself, but the palette can still be changed at startup.) All GBC games (black-cart or clear-cart) have a "forced" color palette that cannot be changed with a button combination. Pokemon Yellow has a multi-color palette that cannot be changed on a GBC/GBA. Again, this behavior is common across all GBC games, and it is not shown in any GB game.

Cartridge Header
http://gbdev.gg8.se/wiki/articles...
The internal code of each GB/GBC game includes a flag to indicate whether a game has GBC features and is/isn't compatible with older monochrome GB systems. Pokemon Yellow's header indicates that it is a backwards-compatible GBC game. (I assume this is how the Game Boy determines whether or not any given game can accept a customizable color palette, so the "forced color palette" issue might simply be an indicator of the cart header.)

Rules for GBC games to use color
https://archive.org/details/GameB...
In the Game Boy Programming Manual v1.1, for developers, there are rules set forth for the use of color. They can be found in the first few pages at the link above. An excerpt:

- Differentiation - If a game is to be considered CGB-compatible, then it must appear significantly more colorful than a monochrome Game Boy game when "colorized" by the CGB hardware. The principal measure of this is the number of colors in the background (BG) and the number of colors in the objects (OBJ).

- Simultaneous Colors - Because CGB hardware automatically "colorizes" monochrome games with up to four colors in the BG palette and up to six colors for two OBJ palettes (three colors per palette), a game typically must display more colors than this automatic "colorization" to be considered a CGB game.

- Appropriate use of Color - Objects in the game that are based on reality (trees, rocks, animals, and so on) should be a color that we would normally associate with them. For fictional objects, colors should be chosen to show appropriate detail and, when needed, to differentiate unlike objects.

- Variety of Colors - The CGB is capable of producing a wide range of colors (32,768 to be exact -albeit not all at the same time). A CGB game should use this capability of the hardware to yield
distinctly different colors for objects, characters, areas, and so on.

Looking at Pokemon Yellow, especially in comparison with Red/Blue and Gold/Silver, it’s plain to see that the capabilities of the GBC are being used, but according to these requirements, they are being underused, such that Yellow would not qualify "to be considered a CGB game."

Red:
https://gamefaqs.akamaized.net/sc...
https://gamefaqs.akamaized.net/sc...

Yellow:
https://gamefaqs.akamaized.net/sc...
https://gamefaqs.akamaized.net/sc...

Silver:
https://gamefaqs.akamaized.net/sc...
https://gamefaqs.akamaized.net/sc...

I confess I haven't done any good research on the extent of game-specific GBC enhancements to GB games, so I can't say for sure if every screen in Yellow could/couldn't technically be displayed with a monochrome GB game being played in a GBC. But why would the game declare itself a GBC game if it doesn't do anything exclusive to GBC hardware? Is it a mistake? Or is it just too minimal to meet the guideline? Either way, it might be a bit of a stretch to say that Pokemon Yellow is "significantly more colorful than a monochrome Game Boy game."


Non-conclusion
Pokemon Yellow is undeniably a special case, with many features that don't match any other GB or GBC game. It seemingly uses features that only the GBC offered, but it was definitely marketed as an original Game Boy game. Is it a forward-compatible GB game? Is it a GBC game demoted by a semantic technicality? Did Game Freak give the ROM to Nintendo as a GBC game, only to see Nintendo take a look at it and decide it didn't meet their color guidelines? Any insights from GB game coders? Or anyone?

Thank you. *byooooooooo*

 

They didn't want to confuse any compatability with Blue/Red to the consumer. They put the original Game Boy logo on the box so people would clearly know it belongs with those games. This game came out 12 months after the GBC launched.

Nice investigation! As noted, it's not close to being as colour-enhanced as the Gen II games, so I personally never thought of it as a GBC game.

Did you read that somewhere, or is it a guess? I can see Nintendo making that decision. It should go in the list if so.

Peko will tell ya all about it.

I asked this question a while back: http://nintendoage.com/forum/mess...

Says Game Boy on the box. Only a total moron would try to argue against that

Wii games are still coming out, so...
 

Never read it anywhere, just my assumption that's why they did it
My point is they wanted people to have absolutely no confusion that the games were fully compatable with the old Red/Blue and worked just the same as they did, so they put the old Game Boy logo on it to remove any casual doubt. If they put the GBC branding on the front there would immediately be casuals/parents who may have an uncertanty when trying to buy their kid such a massively trendy item at that time. It had been a really long gap from October '99 and the last time they'd used that branding on a game so I'm sure they did it just so the box art would align with the other games. It must be why, because Pokemon Pinball was already out the Summer before that in North America, and they used the GBC branding on that.

Lol yep, that's why I included the bit about how popular opinion doesn't mean anything  

I commented in that thread that Yellow was a GBC game, now I at least admit that Nintendo pretended it was GB, and was probably thrilled at the convenience of not having to choose between grey and black.

It could just be a hybrid

Now THAT would be an error.

It's essentially a mislabeled Game Boy game. GBC on the inside, GB on the outside.

Pokemon Yellow is cool but will someone tell me if the Burger King games are truly part of the Xbox 360 set

Somewhere out there, he feels a summoning to this thread.