The newly overhauled demo of this prequel game is out now!
Overhauling the project from scratch for faster gameplay and bug-free experience is quite hard for a solo developer, but here is the new build of Nyghtmare Grave Betrayal [for the Gameboy classic]
It's basically a new game now!
Rom file here!
Get the first game's physical Gameboy Color carts, Nyghtmare the Ninth King on Yastuna Game!