Yenna, Redtooth Regent + Ordeal of Nylea + Tiller Engine + Auratog

Yenna, Redtooth Regent

Ordeal of Nylea

Tiller Engine

Auratog

How it works

1. Activate Yenna by paying 2 and tapping it, creating a token copy of Ordeal of Nylea, then untapping Yenna and causing you to scry 2.
2. Activate Auratog by sacrificing the Ordeal of Nylea token.
3. The Ordeal of Nylea token's second ability triggers, causing you to search your library for two basic land cards and put them onto the battlefield tapped.
4. When the lands enter the battlefield, Tiller Engine triggers twice, untapping them.
5. Resolve the Auratog ability from step 2, giving it +2/+2 until end of turn.
6. Activate the two lands by tapping them, adding 2.
7. Repeat.

This loop relies on Yenna, Redtooth Regent to endlessly duplicate Ordeal of Nylea, feeding each copy to Auratog so you can instantly cash them in for land. While Auratog fuels the sacrifice requirement to trigger the Ordeal's search ability, Tiller Engine acts as the crucial engine piece that catches those fetched lands as they enter tapped and immediately untaps them. This leaves you with free, untapped mana from the lands to continually pay Yenna's activation cost, letting you pull every single basic land out of your deck in one fell swoop.