It was actually being remade as an original game at one point, Penumbra Crystallis, but it just wasn’t working out the way I wanted it to. This remake of the original Blackmoon Prophecy uses assets (many sprites and tiles) from Penumbra Crystallis that I didn’t want to put to waste.
With that said, I also have no intention of this not being a fan game. Fan games are lovely and should be encouraged just as much as fan covers, fan art, cosplay, etc. They are all different methods people use to pay homage to the things they love.