Most played cards in Rakdos:

2 Decks
Badlands
8 copies - 4 average
Dark Ritual
8 copies - 4 average
Sinkhole
8 copies - 4 average
Underworld Dreams
7 copies - 3.5 average
Mishra's Factory
7 copies - 3.5 average
City of Brass
6 copies - 3 average
Red Elemental Blast
5 copies - 2.5 average
Howling Mine
4 copies - 2 average
Disenchant
4 copies - 2 average
Sedge Troll
4 copies - 2 average
Hypnotic Specter
4 copies - 2 average
Swords to Plowshares
4 copies - 2 average
Juzám Djinn
4 copies - 2 average
Lightning Bolt
4 copies - 2 average
Scrubland
4 copies - 2 average
Blood Moon
3 copies - 1.5 average
Drain Life
3 copies - 1.5 average
Winds of Change
3 copies - 1.5 average
Gloom
3 copies - 1.5 average
Icy Manipulator
3 copies - 1.5 average