Here's EGM's review of Ys for the Sega Master System.
I recall wanting a role playing game for SMS during 1989.
I was looking at Miracle Warriors, Ys and Phantasy Star. Honestly, Phantasy Star seemed like obviously the best choice. I'm sure most would agree it was by far the best RPG on Sega's 8-bit console. At that specific time, The TurboGrafx-16 had not yet released in the U.S. although I was aware of the PC-Engine but the TurboGrafx-16 had not even been named or slated for release here. It soon would be though. To me, this new PC-Engine system seemed like a distant Japanese system, wonderful, but unobtainable for someone like me, who only recently got a Master System that year.
When I had fully learned about the Sega Genesis and TurboGrafx-16 with CD-ROM, I could only dream of playing Phantasy Star II and Ys Book I & II on those new systems. It would eventually happen, but not until 1990.