Most played cards in White:

1 Decks
Languish
4 copies - 4 average
Grasp of Darkness
4 copies - 4 average
Caves of Koilos
4 copies - 4 average
Read the Bones
4 copies - 4 average
Gideon, Ally of Zendikar
4 copies - 4 average
Shambling Vent
4 copies - 4 average
Forsaken Sanctuary
4 copies - 4 average
Transgress the Mind
4 copies - 4 average
Oath of Liliana
3 copies - 3 average
Duress
3 copies - 3 average
Liliana, the Last Hope
3 copies - 3 average
Dead Weight
2 copies - 2 average
Kalitas, Traitor of Ghet
2 copies - 2 average
Infinite Obliteration
2 copies - 2 average
Blighted Fen
2 copies - 2 average
Anguished Unmaking
2 copies - 2 average
Sorin, Grim Nemesis
2 copies - 2 average
Ob Nixilis Reignited
2 copies - 2 average
Ruinous Path
2 copies - 2 average
Ultimate Price
2 copies - 2 average