Fertilid + Tireless Provisioner + Roaring Earth + Spelunking

Fertilid

Tireless Provisioner

Roaring Earth

Spelunking

How it works

1. Activate Fertilid by paying 1 and removing a +1/+1 counter from it, causing you to search your library for a basic land card and put it on the battlefield untapped due to Spelunking.
2. When the basic land enters, Tireless Provisioner and Roaring Earth trigger.
3. Resolve the Tireless Provisioner trigger, creating a Treasure token.
4. Activate the Treasure by tapping and sacrificing it, adding .
5. Resolve the Roaring Earth trigger, putting a +1/+1 counter on Fertilid.
6. Activate the basic land by tapping it, adding 1.
7. Repeat.

This loop turns Fertilid into a self-sustaining engine by utilizing Spelunking to ensure every basic land fetched enters the battlefield untapped and ready to contribute mana. As those lands enter, Tireless Provisioner rewards you with Treasure tokens to help fund the activation costs, while Roaring Earth constantly replenishes the +1/+1 counters that Fertilid needs to keep the process going. It's a gorgeous self-contained loop that clears your library of basic lands while generating an overwhelming storm of landfall triggers.