Unlocking Colorblind Accessibility in Puzzle Games through Attrition and Code

Last year, I wrote about colorblind accessibility in Sega Saturn games. Puyo Puyo Tsuu was one of the games I highlighted as being inaccessible for colorblind gamers. I mentioned how Puyo Puyo Tetris improved the shape and definition of the Puyos, but what I didn’t know was that SEGA actually added in colorblind-friendly Alphabet Puyos into the game as an option. I still believe my original solution of defining the eyes/shapes/material of the Puyos would work, but I have to admit, I love what SEGA did to make the game accessible!

Above: Puyos shaped as letters in their Alphabet form!

There is, however, one problem. In order to use Alphabet Puyos, you must first earn 100 credits and buy them through the in-game shop. Earning enough credits isn’t a difficult task (you just need to play around 5 games of Tetris), however, the Alphabet Puyos could easily be unlocked at the start of the game. You start off with multiple types of Puyos and Tetrominoes to use, so why not include the colorblind set?

Many colorblind gamers would either have to stick with Tetris until they get enough credits for the Alphabet Puyos or struggle through Puyo/Puyo Tetris modes. Again, getting 100 credits isn’t a long or difficult task, but when your game is so close to being accessible from the start, why not make it happen? The code to make this possible is changing one value, switching the unlock boolean tied to Alphabet Puyos from false to true.

The same day I learned that Puyo Puyo Tetris gated its colorblind-friendly Puyos, I personally ran into difficulties playing another puzzle game. I am not colorblind and have perfect vision, but occasionally struggle seeing portable games because I need to look down at my feet to play.

I was playing Taito’s Puzzle Bobble Mini (also known as Bust a Move Pocket) on my Neo Geo Pocket Color. The Neo Geo Pocket Color is my favorite handheld system ever, but a notable flaw is the screen is not lit in any way. Playing down at my feet, this can make the system difficult to play in certain conditions. As I was working my way through the game’s puzzle mode, I noticed my bubbles were not popping. In my perspective, I was matching red bubbles to red bubbles and blue bubbles to blue bubbles. In reality, I was matching red bubbles with pink bubbles and blue bubbles with navy bubbles!

Above: The backlit screen of an emulator helps, but imagine playing with no light at your feet.

I couldn’t tell the colors apart but I knew that Puzzle Bobble Mini was forwards compatible with the original Neo Geo Pocket, a system that does not output color. Curious how Puzzle Bobble Mini plays on the original Neo Geo Pocket, I decided to consult the game’s manual to see how it plays on the system.

Above: A comparison of color bubbles and their symbol counterparts.

So as it turns out, Puzzle Bobble Mini changes the color bubbles to symbol bubbles when playing on the original monochrome Neo Geo Pocket! Considering the code to change the bubbles to symbols is already in the game, I went into the options menu figuring that I could enable symbol bubbles on my Neo Geo Pocket Color. Sadly, I learned that changing the bubbles was not an option.

Since I do own an original Neo Geo Pocket, I concluded that I’d be better off experiencing Puzzle Bobble Mini on that system. However, I wasn’t ready to give up on activating symbol bubbles on the Neo Geo Pocket Color! Using my computer, I loaded Puzzle Bobble Mini into a hex editor and began my search for values that would force the game to use symbols. I found out that the ROM header (a small set of values containing various pieces of information about a game) contained a hex value that determines whether or not a game can be played in color. I changed this value, 10 (color compatible) to 00 (monochrome only), and hoped for the best.

Above: Changing a hex value in the ROM header!


After saving my changes along with changing the file extension from .ngc (Color) to .ngp (Original), I booted the game on my Neo Geo Pocket Color emulator. Normally, Puzzle Bobble Mini plays only in color on this emulator. I’m happy to report that the changes I made allowed the game to boot up in monochrome mode! That’s right, changing ONE hex value made the game accessible. I do not own a flash cartridge to test on real hardware, so I can’t say with certainty that the game would also play in monochrome on a real Neo Geo Pocket Color. But given that the game continued to display in monochrome on other emulators, I’d say it’s very likely to behave the same.

Above: Puzzle Bobble Mini successfully booted into monochrome mode!

What I’d love to see is a community effort to enable monochrome modes in retro color-centric games. This extends past the Neo Geo Pocket: there’s hundreds of GameBoy and Wonderswan games that could be modified in the same way. If enabling monochrome gameplay is as easy as switching a hex value in the header globally, I imagine work could be done quickly.
I’d love to see modern color-dependent games offer more ways to play so color isn’t a dependency. Customizable colors and symbols can go a long way! And if a game offers more accessible ways to play, like Puyo Puyo Tetris, it should unlock accessibility from the beginning. Whether it’s an upcoming game or a game released 20 years ago, it’s never too late to be shedding light on vision accessibility! For more information on vision accessibility, check out AbleGamers’ vision accessibility guide over on includification.com.