Most played cards in UR Prowress:

2 Decks
Monastery Swiftspear
8 copies - 4 average
Slip Through Space
8 copies - 4 average
Titan's Strength
8 copies - 4 average
Shivan Reef
8 copies - 4 average
Bloodstained Mire
8 copies - 4 average
Abbot of Keral Keep
8 copies - 4 average
Polluted Delta
8 copies - 4 average
Stormchaser Mage
8 copies - 4 average
Treasure Cruise
7 copies - 3.5 average
Fiery Impulse
7 copies - 3.5 average
Wild Slash
6 copies - 3 average
Self-Inflicted Wound
5 copies - 2.5 average
Duress
4 copies - 2 average
Negate
4 copies - 2 average
Dispel
4 copies - 2 average
Clutch of Currents
4 copies - 2 average
Jace, Vryn's Prodigy
4 copies - 2 average
Expedite
4 copies - 2 average
Roast
4 copies - 2 average
Elusive Spellfist
3 copies - 1.5 average