Most played cards in 5C Control:

3 Decks
Counterspell
12 copies - 4 average
Swords to Plowshares
12 copies - 4 average
City of Brass
11 copies - 3.67 average
Disenchant
11 copies - 3.67 average
Tundra
10 copies - 3.33 average
Volcanic Island
9 copies - 3 average
Red Elemental Blast
9 copies - 3 average
Fellwar Stone
8 copies - 2.67 average
Underground Sea
7 copies - 2.33 average
Fireball
6 copies - 2 average
Blue Elemental Blast
6 copies - 2 average
Power Sink
4 copies - 1.33 average
Divine Offering
4 copies - 1.33 average
Sol'kanar the Swamp King
4 copies - 1.33 average
Control Magic
4 copies - 1.33 average
Earthquake
4 copies - 1.33 average
Mox Ruby
3 copies - 1 average
Mox Pearl
3 copies - 1 average
Mox Sapphire
3 copies - 1 average
Mana Drain
3 copies - 1 average