06/08/18 - 4:00PM ~ 06/18/18 - 3:59PM JST (Quests)
06/08/18 - 4:00PM ~ 06/25/18 - 11:59PM JST (Shop Exchange)
This event will allow you to grind for Marine-clothed characters Natalia, Senel, Sorey, Chloe, Mikleo, Jay, and Genis.
Clearing the quests in the first banner will earn you emblems that will allow you to unlock Natalia (and the materials to awaken her into 6 star quality.)
A total of 100 emblems should earn you Natalia right away, but will need to acquire a total of 24,000 to fully uncap her into a 6 star unit. Additionally, the emblems that you earn can be exchanged for 4 star units Chloe, Jay, Mikleo, Sorey, and Genis:
You will need as many Marine characters possible to be able to challenge the second quest banner in the special quests tab. Doing so will allow you to unlock Senel. While the event quests will be up until June 18th, you will be able to exchange any left over emblems you may have to the shop by 06/25/18.