The Holiday Mystery Box is a special type of rescue, available from January 25, 2013 to January 31, 2013. Because it is not explicitly named a rescue, it is available through the store rather than the rescue page; however, all of its contents are pirates, and could thus be classified as a rescue.
Each Holiday Mystery Box costs 1500 gold coins and contains exactly 1 pirate each. The game advertises it as having a 20% chance of obtaining a super rare. Pirates currently known to be available from the Holiday Mystery Box: