Most played cards in Niv-Mizzet, the Firemind:

1 Decks
Opt
1 copies - 1 average
Muddle the Mixture
1 copies - 1 average
Mizzium Mortars
1 copies - 1 average
Mystic Confluence
1 copies - 1 average
Order of Succession
1 copies - 1 average
Remand
1 copies - 1 average
Preordain
1 copies - 1 average
Ponder
1 copies - 1 average
Miscalculation
1 copies - 1 average
Mana Leak
1 copies - 1 average
Intuition
1 copies - 1 average
Into the Roil
1 copies - 1 average
Impulse
1 copies - 1 average
Izzet Charm
1 copies - 1 average
Lightning Bolt
1 copies - 1 average
Rolling Earthquake
1 copies - 1 average
Magmaquake
1 copies - 1 average
Memory Lapse
1 copies - 1 average
Starstorm
1 copies - 1 average
Mind Stone
1 copies - 1 average