Most played cards in Superfriends:

1 Decks
Oath of Nissa
4 copies - 4 average
Leyline of the Void
4 copies - 4 average
Mindbreak Trap
4 copies - 4 average
Interplanar Beacon
4 copies - 4 average
Karn, the Great Creator
3 copies - 3 average
Ancient Tomb
3 copies - 3 average
Narset, Parter of Veils
3 copies - 3 average
Teferi, Time Raveler
3 copies - 3 average
Swords to Plowshares
3 copies - 3 average
City of Brass
3 copies - 3 average
Humility
3 copies - 3 average
Liliana, the Last Hope
3 copies - 3 average
Ashiok, Dream Render
2 copies - 2 average
Grist, the Hunger Tide
2 copies - 2 average
Sevinne's Reclamation
2 copies - 2 average
Assassin's Trophy
2 copies - 2 average
Prismatic Ending
2 copies - 2 average
Kaya, Orzhov Usurper
2 copies - 2 average
Toxic Deluge
2 copies - 2 average
Marsh Flats
2 copies - 2 average