Talk:FGO 2016 Summer Event Re-Run/@comment-125.227.207.249-20170713114427/@comment-2001:48F8:7024:790:D4F:58A9:A5FC:AB42-20170713142602

Everything in this event is unlocked by farming enough mats to do the development quests (the three green quests at the campfire that give materials). Just keep getting materials until you can do another development quest, and you'll unlock the costume quest.

(To actually purchase the costume, go to the "Enahnce" menu button and it's at the bottom of the list.)