Most played cards in Hive Mind Combo:

3 Decks
Pact of the Titan
12 copies - 4 average
Pact of Negation
12 copies - 4 average
Leyline of Sanctity
12 copies - 4 average
Brainstorm
12 copies - 4 average
Force of Will
12 copies - 4 average
Show and Tell
12 copies - 4 average
Hive Mind
12 copies - 4 average
Ponder
11 copies - 3.67 average
Ancient Tomb
11 copies - 3.67 average
Grim Monolith
9 copies - 3 average
Polluted Delta
8 copies - 2.67 average
City of Traitors
7 copies - 2.33 average
Emrakul, the Aeons Torn
6 copies - 2 average
Pyroclasm
6 copies - 2 average
Gitaxian Probe
6 copies - 2 average
Intuition
6 copies - 2 average
Grafdigger's Cage
5 copies - 1.67 average
Scalding Tarn
5 copies - 1.67 average
Leyline of the Void
4 copies - 1.33 average
Spell Pierce
4 copies - 1.33 average