Astral Dragon, Springheart Nantuko, and Nissa, Resurgent Animist

Prerequisites

• Astral Dragon on the battlefield
• Springheart Nantuko on the battlefield
• Nissa, Resurgent Animist on the battlefield
• if the land card in hand does not enter untapped and/or cannot produce mana available

Steps

1. Play a land
2. When the land enters, Springheart Nantuko and Nissa trigger
3. Holding priority, if the land enters the battlefield untapped, activate it by tapping it, adding at least
4. Resolve the Nissa trigger, adding
5. Resolve the Springheart Nantuko trigger, causing you to pay to create a token copy of Astral Dragon
6. When the Astral Dragon token enters the battlefield, it triggers, creating two copies of a land you control that are 3/3 Dragon creatures in addition to their other types
7. When the land tokens enter the battlefield, Springheart Nantuko and Nissa trigger twice
8. Resolve both Nissa triggers, adding
9. Resolve the first Springheart Nantuko trigger, choosing not to pay and creating a 1/1 Insect creature token
10. Repeat from step 4 with the second Springheart Nantuko trigger

Results

• Infinite ETB
• Infinite creature tokens
• Infinite landfall triggers