The Recruitment Chest is a Chest that contains Legendary Hero Shards.

How to obtain it:

-Go to the Hall of Heroes in your city.
-Tap on the "Recruit Hero" icon.
-Perform recruit operations from (Epic or Advanced Recruitment banners to earn Recruitment Points.
-Once your Recruitment Points reach 100%, you will receive a Recruitment Chest that contains Legendary Hero Shards.
-You can find the chest at the top right of the Recruit screen; tap on it to claim your reward.