Spellbinding Soprano, Sprout Swarm, and Tura Kennerüd, Skyknight

Prerequisites

• Spellbinding Soprano in the graveyard
• Sprout Swarm in hand
• Tura Kennerüd, Skyknight on the battlefield
• You have at least three opponents
• You control at least two untapped creatures, one of which must be green
• available

Steps

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

Results

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