Most played cards in Grixis Control:

1 Decks
Preordain
4 copies - 4 average
Force of Will
4 copies - 4 average
Pyroblast
4 copies - 4 average
Hullbreacher
3 copies - 3 average
By Force
3 copies - 3 average
Volcanic Island
3 copies - 3 average
Scalding Tarn
3 copies - 3 average
Polluted Delta
3 copies - 3 average
Swords to Plowshares
2 copies - 2 average
Flooded Strand
2 copies - 2 average
Dack Fayden
2 copies - 2 average
The Tabernacle at Pendrell Vale
2 copies - 2 average
Ravenous Trap
2 copies - 2 average
Underground Sea
2 copies - 2 average
Soul-Guide Lantern
2 copies - 2 average
Black Lotus
1 copies - 1 average
Mox Jet
1 copies - 1 average
Bolas's Citadel
1 copies - 1 average
Mana Crypt
1 copies - 1 average
Sensei's Divining Top
1 copies - 1 average