How to get multiple puzzle pie...
	Various Google Play Achievemen...

When playing the game once you get past the first twenty levels use your red points to fight all the monster and not the bosses. Once you have all the stages rumbling to fight the boss grind all the bosses only for free exp, money and multiple puzzle pieces of the same card.

Achievement	How to unlock
Arena Champion (1,500 XP)	Win 250 PvP fights.
Arena Hero (2,000 XP)	Win 500 PvP fights.
Arena Ruler (2,500 XP)	Win 1,000 PvP Fights
Arena Veteran (1,000 XP)	Win 100 PvP fights.
Boss of Bosses (2,500 XP)	Win all 100 quests.
Bronze League (1,000 XP)	1st in a bronze league.
Common Cards (1,000 XP)	Collect all common cards.
Gold League (2,000 XP)	1st in a gold league.
Heroic Cards (3,000 XP)	Collect all heroic cards.
Legendary Cards (5,000 XP)	Collect all legendary cards.
Rare Cards (2,500 XP)	Collect all rare cards.
Silver League (1,500 XP)	1st in a silver league.
Standard Cards (1,500 XP)	Collect all standard cards.
Uncommon Cards (2,000 XP)	Collect all uncommon cards.