Board Thread:Update Suggestions/@comment-31561904-20161017070853/@comment-25856498-20161018060505

Invest Chest - When first interacted with (the moment you first tap on it once you've won it), it allows you to "invest" cards, with the maximum amount of storable cards dependent on the Arena you won it in.

You can only invest Common, Rare and Epic cards. The Invest Chest has space for 100, 135, 170, 200, 230, 260, 290, 320 and 380 Common cards for Arenas 1 to 9 respectively. A Rare card is considered to take up space equivalent to 10 Common cards, and an Epic card is considered to take up space equivalent to 200 Common cards.

After you have invested the cards, the chest locks itself, where it will then take 10 hours to unlock. Once unlocked, it gives you back your invested cards as well as a copy of them, effectively doubling your investment. For example, if I invested 30 Knight cards into the chest, I will get 60 Knight cards back when I unlock the chest.

On Problem's scale, it is "Extremely Rare".