Jeskai Ascendancy, and Sprout Swarm

Prerequisites

• Jeskai Ascendancy on the battlefield
• Sprout Swarm in hand
• You control at least five untapped creatures, one of which must be green

Steps

1. Cast Sprout Swarm with buyback by tapping five untapped creatures you control
2. Jeskai Ascendancy's first and second ability triggers
3. Resolve Jeskai Ascendancy's first trigger, untapping all creatures you control and giving them +1/+1 until end of turn
4. Resolve Jeskai Ascendancy's second trigger, allowing you to loot
5. Resolve Sprout Swarm, creating a 1/1 Saproling creature token and returning Sprout Swarm to your hand
6. Repeat

Results

• Infinite creature tokens
• Infinite draw triggers
• Infinite ETB
• Infinite looting
• Infinitely large creatures until end of turn
• Infinite magecraft triggers
• Infinite mana creatures you control can produce
• Infinite storm count
• Infinite untap of all creatures