Most played cards in B/W Aggro:

1 Decks
Kitchen Finks
4 copies - 4 average
Godless Shrine
4 copies - 4 average
Thoughtseize
4 copies - 4 average
Tidehollow Sculler
4 copies - 4 average
Flooded Strand
4 copies - 4 average
Path to Exile
4 copies - 4 average
Dark Confidant
4 copies - 4 average
Bitterblossom
4 copies - 4 average
Fetid Heath
3 copies - 3 average
Chrome Mox
3 copies - 3 average
Umezawa's Jitte
3 copies - 3 average
Smother
3 copies - 3 average
Kataki, War's Wage
3 copies - 3 average
Ethersworn Canonist
3 copies - 3 average
Mortify
3 copies - 3 average
Relic of Progenitus
3 copies - 3 average
Pithing Needle
3 copies - 3 average
Circle of Protection: Red
3 copies - 3 average
Stillmoon Cavalier
2 copies - 2 average
Polluted Delta
2 copies - 2 average