Most played cards in Rest in Pieces:

5 Decks
Force of Will
19 copies - 3.8 average
Flooded Strand
17 copies - 3.4 average
Brainstorm
16 copies - 3.2 average
Swords to Plowshares
15 copies - 3 average
Rest in Peace
15 copies - 3 average
Energy Field
11 copies - 2.2 average
Tundra
11 copies - 2.2 average
Ponder
9 copies - 1.8 average
Meddling Mage
9 copies - 1.8 average
Jace, the Mind Sculptor
9 copies - 1.8 average
Helm of Obedience
8 copies - 1.6 average
Polluted Delta
8 copies - 1.6 average
Stoneforge Mystic
7 copies - 1.4 average
Monastery Mentor
6 copies - 1.2 average
Mindbreak Trap
6 copies - 1.2 average
Counterspell
6 copies - 1.2 average
Enlightened Tutor
5 copies - 1 average
Standstill
4 copies - 0.8 average
Engineered Explosives
4 copies - 0.8 average
Dimir Signet
4 copies - 0.8 average