Collect Mystery Boxes!

March 2015 event
Collect Mystery Boxes is a limited-time event that requires players to simply collect Mystery Boxes spread through each episode to get various rewards. All episodes are eligible for this event, including Ghost Pirate's Island of Coins.

Walkthrough
Contrary to what the newsletter says, the location for each of the mystery boxes are fixed. Here's the position of every mystery boxes available. Alternatively, players can obtain additional Mystery Boxes aside from the fixed location using Adventurer Cookie or the Power+ from L-grade Cookies and Pets.

It is advised to run in Ghost Pirate's Island of Coins to complete the event quickly, as it has shorter time frame between mystery boxes. Also players may want to run on Escape from the Oven using Adventurer Cookie to collection more than three mystery boxes. Unlock King Choco Drop to assist you to get yet another mystery box.

List of Rewards
The game continues to count Mystery Boxes even after 120 boxes have been collected.