Most played cards in Dragon:

1 Decks
Gemstone Mine
4 copies - 4 average
Forbidden Orchard
4 copies - 4 average
Xantid Swarm
4 copies - 4 average
Worldgorger Dragon
4 copies - 4 average
Underground Sea
4 copies - 4 average
Squee, Goblin Nabob
4 copies - 4 average
Elvish Spirit Guide
4 copies - 4 average
Careful Study
4 copies - 4 average
Bazaar of Baghdad
4 copies - 4 average
Animate Dead
3 copies - 3 average
Necromancy
3 copies - 3 average
Stifle
3 copies - 3 average
Dance of the Dead
3 copies - 3 average
Chalice of the Void
3 copies - 3 average
Verdant Force
2 copies - 2 average
Stroke of Genius
2 copies - 2 average
Chain of Vapor
2 copies - 2 average
Echoing Truth
2 copies - 2 average
Sundering Titan
2 copies - 2 average
Null Rod
1 copies - 1 average