Well, I don't see this on the wiki (Altered Beast (home computers)), but I came across this YouTube video: http://m.youtube.com/watch?v=hmZfemAO8nI https://m.youtube.com/watch?v=hmZfemAO8nI The description of the video says this:
It's probably a MSX game, but I'm just going by the video description. EDIT: Yeah, it's MSX. I've updated the topic accordingly.
It's a unlicensed product - it wouldn't qualify for Sega Retro, though is neat in its own little way I guess. Ignoring the fact that there was an officially licensed MSX port http://www.youtube.com/watch?v=04VJS_HHtjY And hey, it's a lazy Spectrum conversion. It's a small world.
Yeah, the OP was confusing to me because I knew a ZX Spectrum port to the MSX existed, but looked nothing like the one in the OP. The original ZX spectrum port of AB is terrible, in case anybody is wondering.