Update, July 25, 2018 (12:55AM EST): Sega confirmed with Polygon that the Phantasy Star mobile game is called Idola: Phantasy Star Saga.
The game looks to be a turn-based RPG that uses the ubiquitous gacha system to unlock and recruit characters. The system implies that the game will be free-to-play, though Sega did not say.
The two main characters are Stella, a leader of the Aries Knights, and Yuri, an orphan who joins the Aries Knights. Along with other characters, they fight the titular Idola monsters and the Dark Falz. As with the gameplay, story details remain light for the time being.
Idola: Phantasy Star will launch in Japan later this year. Sega did not say whether the game would launch in Europe or the U.S., two regions that continue to see a dearth of Phantasy Star titles.
Original article, July 22, 2018 (12:30PM EST): To celebrate the 30th anniversary of its Phantasy Star RPG series, Sega launched a countdown website for what looks to be a Phantasy Star title for Android and iOS.
An official reveal is set for July 24 at 11:00pm EST. Because the website is in Japanese, it is a safe bet that the game will first launch in Japan.
If this turns out to be a port, Sega has a deep well it can reach in. The Phantasy Star series started in 1987 with the original Phantasy Star, and has since spawned three sequels and numerous spin-offs. Then again, the series is due for a new entry. The most recent entry came in 2014 with Phantasy Star Nova for the PS Vita.
The fear is that a new entry could mean we get yet another gacha game, which uses loot boxes as its monetization scheme, or a free-to-play game that really pushes its in-app purchases toward the player.
Whatever the game ends up being, a release in the West would be very welcome. The most recent Phantasy Star game released in the West came in 2010 with Phantasy Star Portable 2 for the PSP. Also keep in mind that Sega promised an English version of Phantasy Star Online 2 several years ago and have not yet delivered on that promise.
Until Sega announces the new Phantasy Star mobile title, you can download Phantasy Star II Online at the link below. The game is free to download, though there are in-app purchases.