Most played cards in UR Aggro:

2 Decks
Lightning Bolt
8 copies - 4 average
Monastery Swiftspear
8 copies - 4 average
Daze
8 copies - 4 average
Delver of Secrets
8 copies - 4 average
Chain Lightning
8 copies - 4 average
Ponder
8 copies - 4 average
Brainstorm
8 copies - 4 average
Force of Will
8 copies - 4 average
Scalding Tarn
7 copies - 3.5 average
Volcanic Island
7 copies - 3.5 average
Stormchaser Mage
6 copies - 3 average
Polluted Delta
5 copies - 2.5 average
Pyroblast
5 copies - 2.5 average
Price of Progress
5 copies - 2.5 average
Smash to Smithereens
5 copies - 2.5 average
Gitaxian Probe
4 copies - 2 average
Surgical Extraction
4 copies - 2 average
Invasive Surgery
3 copies - 1.5 average
Eidolon of the Great Revel
3 copies - 1.5 average
Bedlam Reveler
2 copies - 1 average