When Orzhov Basilica enters the battlefield, it, Springheart Nantuko, and Kodama of the East Tree trigger.
Resolve the Kodama of the East Tree trigger, choosing not to put anything from your hand onto the battlefield.
Resolve the Orzhov Basilica trigger, returning it from the battlefield to your hand.
Resolve the Springheart Nantuko trigger, creating a token.
When the token enters the battlefield, Kodama triggers, putting Orzhov Basilica from your hand onto the battlefield.
When Orzhov Basilica enters the battlefield, it and Springheart Nantuko trigger.
Repeat from step 4.
This clever loop leverages the triggered abilities of Kodama of the East Tree and Springheart Nantuko to turn a single land drop into an infinite cycle of rebirth. When you play Orzhov Basilica, its entry triggers Kodama of the East Tree to let you drop a card and Springheart Nantuko's landfall ability to create a token copy of a creature. That token's entry triggers Kodama of the East Tree once again, allowing you to seamlessly cheat Orzhov Basilica right back onto the battlefield from your hand while it simultaneously returns itself to your hand to fuel the engine.