Most played cards in R/W Control:

3 Decks
Sacred Foundry
12 copies - 4 average
Lightning Helix
12 copies - 4 average
Battlefield Forge
10 copies - 3.33 average
Savannah Lions
8 copies - 2.67 average
Pyroclasm
8 copies - 2.67 average
Soltari Priest
8 copies - 2.67 average
Wrath of God
8 copies - 2.67 average
Knight of the Holy Nimbus
8 copies - 2.67 average
Faith's Fetters
7 copies - 2.33 average
Condemn
7 copies - 2.33 average
Flagstones of Trokair
7 copies - 2.33 average
Firemane Angel
7 copies - 2.33 average
5 copies - 1.67 average
Boros Garrison
5 copies - 1.67 average
Disenchant
5 copies - 1.67 average
Steam Vents
4 copies - 1.33 average
Greater Gargadon
4 copies - 1.33 average
Mana Leak
4 copies - 1.33 average
Compulsive Research
4 copies - 1.33 average
Restore Balance
4 copies - 1.33 average