Most played cards in Esper:

6 Decks
Sunscape Familiar
24 copies - 4 average
Sea Gate Oracle
24 copies - 4 average
Snap
24 copies - 4 average
Compulsive Research
23 copies - 3.83 average
Mulldrifter
23 copies - 3.83 average
Ash Barrens
21 copies - 3.5 average
Lone Missionary
20 copies - 3.33 average
Azorius Chancery
19 copies - 3.17 average
Ghostly Flicker
18 copies - 3 average
Dimir Aqueduct
17 copies - 2.83 average
Evolving Wilds
16 copies - 2.67 average
Preordain
16 copies - 2.67 average
Hydroblast
15 copies - 2.5 average
Dispel
15 copies - 2.5 average
Nightscape Familiar
15 copies - 2.5 average
Prismatic Strands
14 copies - 2.33 average
Mnemonic Wall
13 copies - 2.17 average
Dinrova Horror
13 copies - 2.17 average
Stonehorn Dignitary
13 copies - 2.17 average
Circle of Protection: Blue
12 copies - 2 average