MoGDon't worry, I hadn't heard of it before either. I found out about it because I liked the game
La Mulana, which is made to be like an old MSX game. Which in turn got me interested in an MSX emulator to try some of those games (along with the Ys series...I read a LOT about random crap like this). Anyway, La Mulana was inspired by this Maze of Galious game. So I was looking for the ROM and came across this remake.
I played the ROM first because I wanted to try the emulator (
blueMSX, if you're interested), and I have to say this remake seems quite faithful to the original. They even kept the password saving.
Anyway, the game is kind of a Metroidvania style platformer. You're a knight, you have a sword, you go around the various screens killing bad dudes and finding keys and treasures and stuff to help you get further. Pretty old school, but lots of fun. There are a bunch of different graphics sets that come with it including the original MSX art and you can switch between them on the fly. So check it out.