Most played cards in The Rock:

3 Decks
Pernicious Deed
12 copies - 4 average
Duress
12 copies - 4 average
Birds of Paradise
12 copies - 4 average
Llanowar Wastes
11 copies - 3.67 average
Cabal Therapy
10 copies - 3.33 average
Treetop Village
8 copies - 2.67 average
Ravenous Baloth
8 copies - 2.67 average
Spiritmonger
8 copies - 2.67 average
Windswept Heath
7 copies - 2.33 average
Spike Feeder
5 copies - 1.67 average
Living Wish
5 copies - 1.67 average
Wall of Blossoms
5 copies - 1.67 average
Engineered Plague
5 copies - 1.67 average
Smother
5 copies - 1.67 average
Naturalize
4 copies - 1.33 average
Diabolic Edict
4 copies - 1.33 average
Swords to Plowshares
4 copies - 1.33 average
Barren Moor
4 copies - 1.33 average
Vindicate
4 copies - 1.33 average
Tranquil Thicket
4 copies - 1.33 average