Most played cards in Cephalid Breakfast:

3 Decks
Brainstorm
12 copies - 4 average
Cephalid Illusionist
12 copies - 4 average
Force of Will
12 copies - 4 average
Aether Vial
12 copies - 4 average
Flooded Strand
12 copies - 4 average
Nomads en-Kor
10 copies - 3.33 average
Stoneforge Mystic
10 copies - 3.33 average
Daze
9 copies - 3 average
Tundra
9 copies - 3 average
Narcomoeba
9 copies - 3 average
Eladamri's Call
8 copies - 2.67 average
Misty Rainforest
8 copies - 2.67 average
Leyline of the Void
8 copies - 2.67 average
Cabal Therapy
7 copies - 2.33 average
Detention Sphere
4 copies - 1.33 average
Tropical Island
4 copies - 1.33 average
Polluted Delta
4 copies - 1.33 average
Underground Sea
4 copies - 1.33 average
Dark Confidant
3 copies - 1 average
Phyrexian Revoker
3 copies - 1 average