Kodama of the East Tree and Cloudstone Curio on the battlefield.
An additional nonartifact permanent card in your hand that you are able to play.
An additional nonartifact permanent card on the battlefield that shares a type with the card in your hand and that has an equal or lesser mana cost.
({3} magic symbol) ({U} magic symbol) available.
Steps
Cast Irenicus's Vile Duplication by paying ({3} magic symbol) ({U} magic symbol) , creating a nonlegendary token copy of Kodama of the East Tree with flying.
When the token enters the battlefield, Cloudstone Curio and the original Kodama of the East Tree trigger; decline to use these abilities unless desired.
Play the nonartifact permanent in your hand.
When it enters the battlefield, Cloudstone Curio and both copies of Kodama of the East Tree trigger.
Resolve the Cloudstone Curio trigger, returning the other nonartifact permanent from the battlefield to your hand.
Resolve the first Kodama of the East Tree trigger, putting the permanent you returned in step 5 from your hand onto the battlefield.
When that permanent enters the battlefield, Cloudstone Curio and the second Kodama of the East Tree trigger.
Resolve the Cloudstone Curio trigger, returning the permanent you played in step 3 from the battlefield to your hand.
Resolve the Kodama of the East Tree trigger from step 7, declining to use it unless desired.
Resolve the remaining Kodama of the East Tree trigger from step 4, putting the permanent you returned in step 8 from your hand onto the battlefield.
Repeat from step 4 any number of times.
This combo results in Infinite ETB and Infinite LTB if a permanent involved is a creature, and/or Infinite landfall triggers if it is a land.
Results
Infinite ETB.
Infinite landfall triggers.
Infinite LTB.
Put all permanent cards below a certain mana value from your hand onto the battlefield.