Board Thread:Shadow Fight 2 Discussion/@comment-112.120.149.118-20180123125013/@comment-34224387-20180123165730

Chests are just an organization of different reward tiers. There are 3 types of chests, the first one having minimal rewards, available after beating stage 1 and 2, the second one having medium rewards, available after beating stage 3 and 4, and the third one having the best rewards, available after beating stage 5.

Failing at any stage or beating stage 5 will reset you back to stage 1.

Keep in mind that difficulty increases along with rewards.