Ys III was initially released for the NEC PC-8801 and NEC PC-9801 in 1989, and versions for the MSX 2 and Sharp X68000 soon followed. In 1991, a number of console ports were produced: versions for the TurboGrafx-CD, Famicom, Super NES, and Sega Mega Drive/Genesis. A port for the PlayStation 2 was released by Taito Corporation in 2005.
The TurboGrafx-CD, Super NES, and Genesis versions received official English-translated releases. In addition, the NES and MSX 2 versions have been fan-translated.
The opening scene informs the player that it has been three years since the events of Ys I and Ys II. Adol Christin and his friend Dogi are on a journey to Dogi's hometown of Redmont. Upon arriving, they learn that the townspeople are being threatened by men from nearby Valestine Castle. Always ready for adventure, Adol decides to assume the task of helping them out.
The gameplay of Ys III is a sharp departure from the previous two games. Instead of the previously used top-down camera view, Ys III has become a side-scrolling platform-action styled game. The combat has also changed: the player must push a button to make Adol swing his sword and attack enemies.
The RPG-style statistics and experience system still exists in Ys III, however. A new addition to this area is the "ring" system: Adol can acquire and equip rings that provide special effects while equipped. A new attribute, "Ring Power", is consumed while rings are active.
The soundtrack to the original version of Ys III was entirely composed by Mieko Ishikawa. The Sharp X68000 version of the game introduced a number of additional compositions, which were composed by Masaaki Kawai.
Falcom has released a number of music CDs dedicated to the music of Ys III. They include:
- Music from Ys III: Wanderers from Ys (1989): Soundtrack to the original NEC PC-8801 edition of Ys III, along with three tracks from the X68000 edition.
- Wanderers from Ys Super Arrange Version (1989): A collection of arranged tracks from Ys III by Hiroyuki Nanba and Atsushi Yokozeki.
- Ys III J.D.K. Special (1990): The complete soundtrack to the X68000 version of Ys III, along with four rock music arrangements from Falcom's J.D.K. Band.
- Perfect Collection Ys III (1990): A two-CD set entirely dedicated to Ys III. The first disc is a complete arrangement of the Ys III soundtrack, including the X68000-introduced tracks, by Ryo Yonemitsu (who was also responsible for arranging the TurboGrafx-CD version's Redbook audio tracks) and two others. The second disc contains additional Ys III arrangements in various musical styles.
To commemorate the release of the Ys III remake The Oath in Felghana in 2005 (see below), Falcom released Ys Premium Music CD Box in Felghana, a boxed set of all Ys III music CDs produced.
Ys: The Oath in Felghana
In 2005, Falcom released Ys: The Oath in Felghana for Microsoft Windows, a heavily re-imagined remake of Ys III. The Oath in Felghana slightly modifies and greatly expands on the story of the original Ys III, and expands the dungeons to extend the gameplay time. The original side-scroller was also replaced with a 3D game engine, based on that used in Ys: The Ark of Napishtim.