At the Kyoto International Manga Anime Fair which took place on 17 September 2017, Fate/Grand Order Japan officially announced that the game has hit the 10 million download mark in Japan alone. Seen as an achievement worth celebrating, the developer is holding an event as a thanks to its player base.
So to commemorate the 10 million download milestone in Japan, players who have completed the “特異点F 炎上汚染都市 冬木” mission will get one (1) free ★4(SR) of their choice, from a pool of 42, as shown below. To sweeten things, players will also be getting a total of 30 gems on 24 September 2017 for free, which was a reward from a previous retweet event.
Sometime in the middle of October 2017, Fate/Grand Order Japan will be continuing its main story with Epic of Remnant “亜種特異点III, 屍山血河舞台, 下総国, 英霊剣豪七番勝負”, so look forward to that as well.