Saw in Half + Myr Battlesphere + Purphoros, God of the Forge + Primal Vigor
Saw in Half
Myr Battlesphere
Purphoros, God of the Forge
Primal Vigor
Near-infinite damage
How it works
Cast Saw in Half by paying 2, destroying Myr Battlesphere and creating four token copies of it with base power and toughness equal to half the original Myr Battlesphere's power and toughness, rounded up.
When the Myr Battlesphere tokens enter the battlefield, each token triggers once and Purphoros triggers four times.
Resolve each Myr Battlesphere trigger, creating a total of 32 1/1 Myr artifact creature tokens, and triggering Purphoros 32 additional times.
Resolve all 36 Purphoros triggers, dealing 72 damage to each opponent.