Play a land. When the land enters, Springheart Nantuko triggers, causing you to pay 1 to create a token copy of Dryad Arbor.
When the Dryad Arbor token enters, Springheart Nantuko triggers. Holding priority, activate the Dryad Arbor token by tapping it, adding .
Zendikar Resurgent triggers, adding .
Resolve the Springheart Nantuko trigger, causing you to pay 1 to create a token copy of Dryad Arbor.
Repeat from step 2.
This loop turns a simple land drop into an engine of endless growth by leaning on Zendikar Resurgent to double every drop of green mana you generate, allowing you to pay for Springheart Nantuko's landfall ability indefinitely. Each iteration spawns a fresh Dryad Arbor token, which simultaneously triggers the Nantuko while its own tap-ability is fueled by Zendikar Resurgent's mana-doubling trigger to sustain the loop. Meanwhile, Purphoros, Bronze-Blooded quietly ensures that any other threats you drop along the way immediately reap the benefits of haste, making this recursive token factory a devastatingly explosive win condition.