These two games aren't really all that similar, but both are amazing. If I had to choose one, I'd probably go with Ys. Zelda's gameplay mechanics win, hands down, as do Zelda's puzzles. But Ys's atmosphere, dungeon complexity, cutscenes, soundtrack and overall presentation are something that's hard for *any* 16-bit era game to touch. To this day, I still consider the Ys Book I & II soundtrack one of the greatest video game OSTs ever created. With Ys, I had this looming feeling that something BIG, IMPORTANT and EPIC was happening. With Zelda LttP, I already knew what was going to happen before I even put the cartridge in the SNES... I was going to complete the Triforce and go kill Gannon.