Spellbinding Soprano + Sprout Swarm + Young Pyromancer

Prerequisites

• You have at least three opponents.
• You control an untapped green creature.

Steps

1. 1Activate Spellbinding Soprano's encore ability by paying and exiling it from your graveyard, creating two token copies of it with haste for each opponent you have.
2. 2Declare each Spellbinding Soprano token as an attacker.
3. 3Each Spellbinding Soprano token triggers, causing instant and sorcery spells you cast this turn to cost less to cast for each Spellbinding Soprano token.
4. 4Cast Sprout Swarm with buyback by tapping a green creature and any other creature you control.
5. 5Young Pyromancer triggers, creating a 1/1 Elemental creature token.
6. 6Resolve Sprout Swarm, creating a 1/1 Saproling creature token and returning Sprout Swarm to your hand.
7. 7Repeat from step 4.

Effects

• Infinite ETB
• Infinite magecraft triggers
• Infinite storm count
• Infinite tapped creature tokens