Fertilid + Nissa, Resurgent Animist + Roaring Earth + Horizon Explorer

Fertilid

Nissa, Resurgent Animist

Roaring Earth

Horizon Explorer

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 Horizon Explorer.
2. When the basic land enters, Nissa and Roaring Earth trigger.
3. Resolve the Nissa trigger, adding .
4. Resolve the Roaring Earth trigger, putting a +1/+1 counter on Fertilid.
5. Activate the basic land by tapping it, adding 1.
6. Repeat.