Most played cards in Turbo Depths:

1 Decks
Duress
4 copies - 4 average
Pithing Needle
4 copies - 4 average
Vampire Hexmage
4 copies - 4 average
Verdant Catacombs
4 copies - 4 average
Thoughtseize
4 copies - 4 average
Deathrite Shaman
4 copies - 4 average
Dark Confidant
4 copies - 4 average
Dark Depths
4 copies - 4 average
Crop Rotation
4 copies - 4 average
Thespian's Stage
4 copies - 4 average
Urborg, Tomb of Yawgmoth
3 copies - 3 average
Abrupt Decay
3 copies - 3 average
Toxic Deluge
2 copies - 2 average
Bitterblossom
2 copies - 2 average
Rite of Consumption
2 copies - 2 average
Surgical Extraction
2 copies - 2 average
Tireless Tracker
2 copies - 2 average
Grafdigger's Cage
2 copies - 2 average
Sylvan Safekeeper
2 copies - 2 average
Sylvan Scrying
2 copies - 2 average