When Dimir Aqueduct 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 Dimir Aqueduct 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 Dimir Aqueduct from your hand onto the battlefield.
When Dimir Aqueduct enters the battlefield, it and Sarinth Greatwurm trigger.
Repeat from step 4.
This clever loop turns the self-bouncing nature of Dimir Aqueduct into an engine for infinite resources by leveraging the passive presence of Sarinth Greatwurm and Kodama of the East Tree. Every time the Aqueduct enters the battlefield, it triggers its own bounce ability while Sarinth Greatwurm watches lands arrive to continually spawn tapped Powerstone tokens. Those newly created tokens entering the battlefield then satisfy Kodama of the East Tree's triggered ability, allowing you to instantly drop the bounced Dimir Aqueduct right back into play to keep the cycle spinning endlessly.