Lumra, Bellow of the Woods + Famished Worldsire + Eldrazi Confluence + Eternal Witness + Spelunking

Lumra, Bellow of the Woods

Famished Worldsire

Eldrazi Confluence

Eternal Witness

Spelunking

How it works

1. Activate any number of lands by tapping them, adding at least 2.
2. Cast Eldrazi Confluence by paying 2, selecting its second mode three times, blinking Lumra, Eternal Witness and Famished Worldsire.
3. As Famished Worldsire enters, choose to sacrifice at least the lands tapped for mana in step 1, causing Famished Worldsire to then enter with three +1/+1 counters for each land sacrificed.
4. When Lumra, Eternal Witness and Famished Worldsire enter, they each trigger.
5. Resolve the Lumra trigger, causing you to mill four cards and return all land cards from your graveyard to the battlefield untapped due to Spelunking.
6. Resolve the Eternal Witness trigger, returning Eldrazi Confluence from your graveyard to your hand.
7. Resolve the Famished Worldsire trigger, causing you to look at some cards from the top of your library and put any land cards from among them onto the battlefield untapped due to Spelunking.
8. Repeat.

This brilliant loop puts Spelunking's static ability to work by ensuring that every land entering the battlefield comes in untapped instead of tapped, turning a cascade of landfall effects into a free-flowing reservoir of resources. You cast Eldrazi Confluence to simultaneously blink Lumra, Bellow of the Woods, Eternal Witness, and Famished Worldsire. As Famished Worldsire enters, its devour mechanic consumes your lands to grow massive, which in turn supercharges its triggered ability to dig deep into your library for even more lands. Meanwhile, Lumra, Bellow of the Woods mills your deck and plucks every single land right back out of your graveyard, while Eternal Witness handily loops Eldrazi Confluence back to your hand so you can repeat the whole spectacle indefinitely.