Cultivator Colossus

Trample
Cultivator Colossus's power and toughness are each equal to the number of lands you control.
When this creature enters, you may put a land card from your hand onto the battlefield tapped. If you do, draw a card and repeat this process.

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The process is repeated until you decline to put a land card onto the battlefield.

You repeat the process as part of Cultivator Colossus's triggered ability's resolution. If the land you put onto the battlefield caused any abilities to trigger, those abilities won't go on the stack until after the ability has finished resolving.