She traverses between planets, gathering a party of fighters and collecting the items she needs to avenge her brother's death and return peace to the star system.

Sega launched the development of Phantasy Star so their Master System could compete with the burgeoning popularity of console RPGs, particularly Dragon Quest (1986) on the Famicom.

The team wanted Phantasy Star to be a unique RPG experience, so they added elements like 3D dungeon crawling, a female protagonist, and ample animation.

The battery backup system drew praise but also contributed to the game's notably high retail price which made it difficult for some critics to recommend.

[4][8][9] When an enemy is defeated, party members gain experience points and are rewarded with a treasure chest that may contain money or a booby trap.

Together, they embark on an adventure spanning the three planets, meeting with townspeople, battling enemies, and finding special items that will help in the fight against Lassic.

[11] Enix's Dragon Quest series was proving to be very popular on the Famicom,[11][12] inspiring other developers to design similar games.

[11] Around the release of Dragon Quest II in January 1987, Sega felt they needed an RPG for their Master System to compete in this emerging market.

[11][14] They had previously been recognized for their work within Sega — Hayashida for Alex Kidd in Miracle World (1986),[10][11] and Naka for his 8-bit home console conversions of arcade games like Out Run and Space Harrier.

[10][11] Other staff members from Miracle World joined the project including lead graphic designer Rieko Kodama, and composer Tokuhiko Uwabo.

[13] Among them were Kodama, who drew most of the artwork,[12] designer Miki Morimoto, who did much of the playtesting and enemy statistics configuration,[13] and Chieko Aoki, who wrote the game's original story and script.

The team was strongly influenced by Star Wars and how it combined Western culture with Japanese touches, such as how clothing resembled judo uniforms, and lightsabers were used like samurai swords.

[10][12] Kodama took this approach and designed the world of Phantasy Star using a science fiction motif mixed with medieval fantasy elements.

[13] The team drew inspiration from Western dungeon crawling RPGs like Wizardry and wanted to add animated navigation to help the player know their location and orientation more easily.

Typically these scenes were rendered in small boxes, so Naka was motivated to engineer a full-screen dungeon that could be used for an action game or an RPG.

[11] Originally the artists were drawing full 2D backgrounds using a 3D perspective, but the number of frames necessary to achieve the animated effect used too much space on the cartridge.

[11] Composer Uwabo noted that the game was developed during the Japanese economic bubble, which fueled his enthusiasm which he believes is reflected in the music.

[20] The game was compatible with the Master System FM synthesis expansion unit which housed a Yamaha YM2413 chip that added nine more mono channels to the console's programmable sound generator (PSG), the SN76489.

[11] The game was released in the West in November 1988, introducing players outside Japan to the emerging JRPG scene, having been localized before Dragon Quest or Final Fantasy.

[23] Since the original Western release retained the text formatting of the Japanese version, it used fewer characters than a proper English translation required.

In 2008, fans modified the text engine to fit longer lines of dialogue, and released a newly translated version with the Japanese FM soundtrack as well.

[11][25] Phantasy Star also appeared in emulated form on Sonic's Ultimate Genesis Collection for the Xbox 360 and PlayStation 3,[11] and on the Wii via the Virtual Console in 2009.

[24][27][15] This version includes enhancements such as options to make the game easier and faster, guides for items, spells, and monsters, the FM soundtrack, hiragana support, and a dungeon auto-mapping feature.

Computer Gaming World called it "the big shot in the arm for Sega [...] who was, at that time, being buried under a ton of NES titles and aggressive marketing".

[5][7] VideoGames & Computer Entertainment and S: The Sega Magazine praised the game for being easy to play and not relying on quick action reflexes.

[7][6][5][33] VideoGames & Computer Entertainment commended the mix of science fiction and fantasy elements, and felt it had a grander scale than other RPGs.

[6][5][38] Electronic Game Player called Phantasy Star a "visual tour-de-force" and "so technologically superior in graphics, that the Nintendo titles pale by comparison".

[40][9] Nintendo Life felt that the graphics did show their age, but noted that it "looks much better than an 8-bit RPG has any right to and it easily surpasses any NES effort of the era".

[42][40][43] The Game Boy Advance version was commended for being a good emulation but criticized for poor sound and missed opportunities for enhancements.

[40][39] Nintendo World Report praised the Switch release for adding FM sound and enhancements to make for a more streamlined experience.