Talk:Underground Treasure Chest 4/@comment-175.156.127.5-20160415075928/@comment-27434399-20160415080824

Most likely for May's Juzumaru's event. Previously, there's a bead event that we have only 6 daily passes to enter the event to get beads for rewards. The passes are given twice per day, 3 passes each time slot.

Technically it's impossible to get all rewards based on free passes, the kobans are used to get more passes to participate the event.

Of course, you can also use them to buy backgrounds. c: