Most played cards in GW Depths:

2 Decks
Swords to Plowshares
8 copies - 4 average
Knight of the Reliquary
8 copies - 4 average
Green Sun's Zenith
8 copies - 4 average
Elvish Reclaimer
8 copies - 4 average
Windswept Heath
8 copies - 4 average
Crop Rotation
7 copies - 3.5 average
Wasteland
6 copies - 3 average
Thespian's Stage
6 copies - 3 average
Mox Diamond
6 copies - 3 average
Yavimaya, Cradle of Growth
6 copies - 3 average
Savannah
6 copies - 3 average
Legolas's Quick Reflexes
6 copies - 3 average
Dark Depths
6 copies - 3 average
Endurance
5 copies - 2.5 average
Force of Vigor
4 copies - 2 average
Sejiri Steppe
4 copies - 2 average
Veil of Summer
4 copies - 2 average
Sylvan Library
4 copies - 2 average
Flagstones of Trokair
4 copies - 2 average
Deafening Silence
4 copies - 2 average