MementosG 5

Mementos G5:
Complete three different collections.

Easiest way to get this is to always play on the highest venue you have unlocked and only using your keys on said venue. The higher the venue, the more coins, tickets, and keys you can win, thus allowing you to build up your stock and stay in the game until you have blacked out all boards. In doing so you will end up with 50+ chest at the end and will end up with at least 1 or 2 pieces of a collection while you are trying to level up and unlock the next venue.

Once you hit level 46, just go back to the venues you have the fewest pieces remaining and grind till you get all 10.

ALSO, if you have already gotten this on the Windows 8 version.

Credit goes to MiniHorseRodeo