Most played cards in Terrageddon:

3 Decks
Swords to Plowshares
12 copies - 4 average
Wasteland
12 copies - 4 average
Mox Diamond
11 copies - 3.67 average
Terravore
11 copies - 3.67 average
Armageddon
10 copies - 3.33 average
Werebear
10 copies - 3.33 average
Windswept Heath
9 copies - 3 average
Mental Note
8 copies - 2.67 average
Yavimaya Coast
8 copies - 2.67 average
Brushland
8 copies - 2.67 average
Weathered Wayfarer
7 copies - 2.33 average
Birds of Paradise
7 copies - 2.33 average
Mystic Enforcer
6 copies - 2 average
Naturalize
6 copies - 2 average
Fact or Fiction
6 copies - 2 average
Enlightened Tutor
5 copies - 1.67 average
Flooded Strand
5 copies - 1.67 average
Mother of Runes
4 copies - 1.33 average
Tranquil Thicket
4 copies - 1.33 average
Gemstone Mine
4 copies - 1.33 average