Most played cards in BW Control:

3 Decks
Swords to Plowshares
12 copies - 4 average
Scrubland
12 copies - 4 average
Disenchant
12 copies - 4 average
City of Brass
10 copies - 3.33 average
White Knight
8 copies - 2.67 average
Circle of Protection: Red
8 copies - 2.67 average
Order of Leitbur
8 copies - 2.67 average
Divine Offering
7 copies - 2.33 average
Sinkhole
7 copies - 2.33 average
City in a Bottle
6 copies - 2 average
Serra Angel
6 copies - 2 average
Hymn to Tourach
6 copies - 2 average
Ivory Tower
6 copies - 2 average
The Abyss
5 copies - 1.67 average
Dark Ritual
4 copies - 1.33 average
Underworld Dreams
4 copies - 1.33 average
Hypnotic Specter
4 copies - 1.33 average
Ashnod's Transmogrant
4 copies - 1.33 average
Su-Chi
4 copies - 1.33 average
Savannah Lions
4 copies - 1.33 average