Most played cards in Red Deck Wins:

3 Decks
Price of Progress
12 copies - 4 average
Lightning Bolt
12 copies - 4 average
Tormod's Crypt
11 copies - 3.67 average
Gorilla Shaman
9 copies - 3 average
Magus of the Moon
8 copies - 2.67 average
Mogg Fanatic
8 copies - 2.67 average
Simian Spirit Guide
8 copies - 2.67 average
Grim Lavamancer
8 copies - 2.67 average
Ankh of Mishra
8 copies - 2.67 average
Fireblast
7 copies - 2.33 average
7 copies - 2.33 average
Pyroblast
7 copies - 2.33 average
Pyrostatic Pillar
6 copies - 2 average
Red Elemental Blast
6 copies - 2 average
Shattering Spree
6 copies - 2 average
Black Vise
5 copies - 1.67 average
Chain Lightning
4 copies - 1.33 average
Lava Spike
4 copies - 1.33 average
Flame Rift
4 copies - 1.33 average
Seal of Fire
4 copies - 1.33 average