Most played cards in Prison Song:

3 Decks
Winter Orb
12 copies - 4 average
Tundra
12 copies - 4 average
Howling Mine
12 copies - 4 average
Disenchant
12 copies - 4 average
Relic Barrier
12 copies - 4 average
Swords to Plowshares
12 copies - 4 average
Icy Manipulator
11 copies - 3.67 average
Power Sink
10 copies - 3.33 average
Fellwar Stone
10 copies - 3.33 average
Tropical Island
10 copies - 3.33 average
Armageddon
9 copies - 3 average
Titania's Song
7 copies - 2.33 average
Dust to Dust
6 copies - 2 average
Wrath of God
6 copies - 2 average
Tranquility
5 copies - 1.67 average
Savannah
5 copies - 1.67 average
City in a Bottle
4 copies - 1.33 average
Timetwister
3 copies - 1 average
Ivory Tower
3 copies - 1 average
City of Brass
3 copies - 1 average