When Izzet Boilerworks enters the battlefield, it, Sarinth Greatwurm, 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 Izzet Boilerworks trigger, returning it from the battlefield to your hand.
Resolve the Sarinth Greatwurm trigger, creating a token.
When the token enters the battlefield, Kodama triggers, putting Izzet Boilerworks from your hand onto the battlefield.
When Izzet Boilerworks enters the battlefield, it and Sarinth Greatwurm trigger.
Repeat from step 4.
This clever loop turns the self-bouncing nature of Izzet Boilerworks into a perpetual motion machine, fueled entirely by the watchful presence of Kodama of the East Tree and Sarinth Greatwurm. When Izzet Boilerworks enters the battlefield, its triggered ability returns it to your hand, while Sarinth Greatwurm creates a tapped Powerstone token in response to the land entry. That newly minted token entering the battlefield then satisfies Kodama of the East Tree's trigger condition, allowing you to instantly drop Izzet Boilerworks right back onto the battlefield from your hand to repeat the cycle infinitely.