McDonald's releases new free-to-play web browser game, "Grimace's Birthday", developed as a new GameBoy Color ROM in 2023
McDonald's opened a new website titled "grimacesbirthday.com", and users are greeted with a surplus of ad-like images containing McDonald's marketing material, and the most interesting of all, is a free-to-play game in the website, appropriately titled "Grimace's Birthday". At first glance, and for those who have been in the internet for quite some time, the title might seem like your typical Java or Flash game running in the website, but the reality of it is entirely different.
"Grimace's Birthday" is actually an entirely new GameBoy Color ROM developed by Krool Toys, a new release for the GBC system in 2023, more than 2 decades after the device has been out of stores.
Those interested in playing the game can do so directly through McDonald's website, but a dump of the game has also been making its rounds online in ROM format.
UPDATE: The game "Grimace's Birthday" was made specifically for this celebration in 2023, and it was done with the use of GB Studio.
Grimace's Birthday website
GB Studio Central article