It’s been four years since Square Enix launched the mobile game Kingdom Hearts Union χ, and they’re celebrating the anniversary by hosting a special anniversary event.

The game, which is a mobile version of the now-defunct browser game Kingdom Hearts χ, was released in North America on April 7, 2016 – four years ago today.

The event features a time-limited “Organization XIII Battle Event,” where players fight to defeat all members of the sinister organization for rewards, along with a “Kingdom Hearts III Quiz Event,” which lets players earn in-game prizes by answering questions about the latest installment in the series.

There’s also an anniversary log-in bonus that will give all players 10,000 jewels, along with a giveaway that will distribute an additional 2 million jewels among 200 lucky players.

On top of that, the anniversary will feature a Hades Cup Event, a variety of Fourth Anniversary Celebration Quests, a “Big Bonus” Challenge Event, and a number of new and returning avatar boards.

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