Most played cards in W/R Midrange:

1 Decks
Caves of Koilos
4 copies - 4 average
Needle Spires
4 copies - 4 average
Rending Volley
4 copies - 4 average
Secure the Wastes
4 copies - 4 average
Gideon, Ally of Zendikar
4 copies - 4 average
Battlefield Forge
4 copies - 4 average
Archangel Avacyn
4 copies - 4 average
Hedron Crawler
4 copies - 4 average
Stasis Snare
3 copies - 3 average
Hangarback Walker
3 copies - 3 average
Reality Smasher
3 copies - 3 average
Thought-Knot Seer
3 copies - 3 average
Declaration in Stone
3 copies - 3 average
Chandra, Flamecaller
3 copies - 3 average
Hallowed Moonlight
2 copies - 2 average
Incendiary Flow
2 copies - 2 average
Planar Outburst
2 copies - 2 average
Nahiri, the Harbinger
2 copies - 2 average
Westvale Abbey
2 copies - 2 average
Gisela, the Broken Blade
1 copies - 1 average