Most played cards in Depths:

1 Decks
Thoughtseize
4 copies - 4 average
Crop Rotation
4 copies - 4 average
Swords to Plowshares
4 copies - 4 average
Windswept Heath
4 copies - 4 average
Knight of the Reliquary
4 copies - 4 average
Green Sun's Zenith
4 copies - 4 average
Elvish Reclaimer
4 copies - 4 average
Thespian's Stage
3 copies - 3 average
Orcish Bowmasters
3 copies - 3 average
Wasteland
3 copies - 3 average
Endurance
3 copies - 3 average
Mox Diamond
3 copies - 3 average
Yavimaya, Cradle of Growth
2 copies - 2 average
Savannah
2 copies - 2 average
Force of Vigor
2 copies - 2 average
Flagstones of Trokair
2 copies - 2 average
Bayou
2 copies - 2 average
Veil of Summer
2 copies - 2 average
Dark Depths
2 copies - 2 average
Sejiri Steppe
2 copies - 2 average