Most played cards in Dream Halls:

32 Decks
Conflux
128 copies - 4 average
Show and Tell
128 copies - 4 average
Brainstorm
128 copies - 4 average
Dream Halls
126 copies - 3.94 average
Force of Will
124 copies - 3.88 average
Progenitus
114 copies - 3.56 average
Ponder
108 copies - 3.38 average
Ancient Tomb
99 copies - 3.09 average
Cruel Ultimatum
74 copies - 2.31 average
Lotus Petal
71 copies - 2.22 average
Spell Pierce
64 copies - 2 average
Lim-Dûl's Vault
61 copies - 1.91 average
Polluted Delta
58 copies - 1.81 average
Thoughtseize
58 copies - 1.81 average
Misty Rainforest
53 copies - 1.66 average
Scalding Tarn
53 copies - 1.66 average
Underground Sea
52 copies - 1.63 average
Flooded Strand
49 copies - 1.53 average
Intuition
45 copies - 1.41 average
Daze
36 copies - 1.13 average