https://en.wikipedia.org/wiki/Dragalia_Lost

Dragalia Lost is an action role-playing game developed and published by Nintendo, in collaboration with Cygames, for Android and iOS. It was initially released in select regions on September 27, 2018. The game is a result between a partnership of Nintendo and Cygames to develop a new mobile game, the first game with another company after Nintendo's initial partnership with DeNA in 2015, which continued for other games.

The story takes place in Alberia, the kingdom where dragons live. All royal members in Alberia have the Dragon Transformation ability, where they can wield a dragon’s power by forming a pact with a dragon to borrow their form in battle. One day, a strange occurrence begins to happen in this kingdom. The Holy Shard protected by the capital starts to lose its power. In order to save his people, the Seventh Prince, who has not made a pact with a dragon, sets off on his Dragon Selection Trial.

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