Most played cards in Spirits:

1 Decks
Spell Queller
4 copies - 4 average
Noble Hierarch
4 copies - 4 average
Supreme Phantom
4 copies - 4 average
Collected Company
4 copies - 4 average
Path to Exile
4 copies - 4 average
Drogskol Captain
4 copies - 4 average
Mausoleum Wanderer
4 copies - 4 average
Flooded Strand
4 copies - 4 average
Horizon Canopy
3 copies - 3 average
Geist of Saint Traft
3 copies - 3 average
Aether Vial
3 copies - 3 average
Phantasmal Image
3 copies - 3 average
Windswept Heath
3 copies - 3 average
Rest in Peace
3 copies - 3 average
Stony Silence
3 copies - 3 average
Unified Will
2 copies - 2 average
Dromoka's Command
2 copies - 2 average
Thalia, Guardian of Thraben
2 copies - 2 average
Selfless Spirit
2 copies - 2 average
Botanical Sanctum
2 copies - 2 average