東方天空璋 Hidden Star in Four Seasons./ Touhou Tenkuushou: Hidden Star in Four Seasons

Touhou Tenkuushou ~ Hidden Star in Four Seasons is the 16th game in the Touhou Project series. It was announced on the developer ZUN's blog on April 20, 2017. A playable demo was released on May 7, 2017, at Reitaisai 14, and the full version was released at Comiket 92 on August 11, 2017. The game was released on Steam worldwide on November 17, 2017, becoming the first game in the series to be available on the platform.

Despite it being midsummer, the seasons in various locations are completely out of whack. The Hakurei Shrine is showered in cherry petals, the Youkai Mountain is basking in the middle of autumn, and the Forest of Magic is blanketed in snow... and thanks to some strange force, Gensoukyou's fairies are running rampant with unfathomable strength. In the midst of this undeniable incident, the girls set out to investigate and find the perpetrator behind it.