Magosi, the Waterveil + The Ozolith + Contagion Engine + Nature's Revolt

Magosi, the Waterveil

The Ozolith

Contagion Engine

Nature's Revolt

How it works

1. During your precombat main phase, activate Contagion Engine by paying 6 and tapping it, putting two eon counters on Magosi.
2. Activate Magosi's third ability by tapping it, removing an eon counter from it and returning it from the battlefield to your hand.
3. When Magosi leaves the battlefield, The Ozolith's first ability triggers, putting an eon counter on The Ozolith.
4. Resolve the Magosi ability, causing you to take an extra turn after this one.
5. Play Magosi.
6. At the beginning of your combat phase, The Ozolith triggers, putting two eon counters on Magosi.
7. Repeat each turn.

This clever setup turns a quirky land into an engine for infinite turns by taking advantage of how permanents interact with counters and zone changes. Because Nature's Revolt turns all lands into 2/2 creatures, Magosi, the Waterveil counts as a creature, allowing The Ozolith to catch its eon counters when Magosi leaves the battlefield. Instead of paying the usual heavy price of skipping a turn, you use Contagion Engine to artificially double up on those eon counters so you can bounce Magosi back to your hand and replay it every cycle. The Ozolith then dutifully returns the accumulated counters right back onto Magosi at the start of combat, letting you repeat the whole loop to take all the time in the world.