From GameBrew - a wiki dedicated to Video Game Homebrew.
Colouredgbc is a coloured carts with the GBC banner to be displayed on the 3DS.
It was initially written for Gen 1 and 2 Pokemon console injects (as GBC banner was in grayscale while GB one is RGB), however it works with the official GBC VC as well.
It is recommended to use Kuriimu 3DS replacing the images Ohana 3DS doesn't replace all three cart images also, because all you are doing is editing the banner.bin.
You can use Ba-GUI-nnertool 3DS to extract the banner.bin included in the download and to repack the banner.bin as well. In order to do so you will also need to extract and rebuilt a CIA file.
- Kuriimu 3DS - A general purpose game translation toolkit for authors of fan translations.
- Ba-GUI-nnertool 3DS - Extract, Customize, Re-Build .cia. Able to create/customize 2D Banner, 3D Banner, Icon/smdh, extract banner.bnr from any decrypted .cia.
- New Super Ultimate Injector 3DS - Tool create installable games from certain older consoles (virtual console/VC injects) on a 3DS Family system.