Fertilid + Tireless Provisioner + Spelunking + Thranduil's Company

Fertilid

Tireless Provisioner

Spelunking

Thranduil's Company

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 Thranduil's Company trigger.
3. Resolve the Tireless Provisioner trigger, creating a Treasure token.
4. Resolve the Thranduil's Company trigger, putting two +1/+1 counters on Fertilid.
5. Activate the basic land by tapping it, adding 1.
6. Activate the Treasure by tapping and sacrificing it, adding .
7. Repeat.

This ingenious engine turns a simple land search into a self-sustaining loop by using Spelunking to ensure your lands enter untapped, generating the exact mana you need to keep going. Whenever that basic land enters the battlefield, Tireless Provisioner rewards you with a Treasure token to fund your next activation, while Thranduil's Company reinforces Fertilid with fresh +1/+1 counters to replace the one you just removed. Meanwhile, Thranduil's Company also works alongside your other Elves to let you play extra lands each turn, and Fertilid does the heavy lifting of pulling every single basic land straight out of your library.