The World Spell + Cloudstone Curio + Lithoform Engine + Estrid's Invocation + Altar of the Brood

The World Spell

Cloudstone Curio

Lithoform Engine

Estrid's Invocation

Altar of the Brood

How it works

1. At the beginning of your precombat main phase, The World Spell triggers, putting a lore counter on itself.
2. The World Spell's third chapter ability triggers.
3. Holding priority, activate Lithoform Engine's first ability by paying 2 and targeting it, copying The World Spell's trigger.
4. Resolve the copy of The World Spell's trigger, putting Estrid's Invocation and any non-Saga enchantment onto the battlefield from your hand.
5. Choose to have Estrid's Invocation enter the battlefield as a copy of The World Spell, with three lore counters due to its read-ahead ability.
6. Estrid's Invocation triggers once, and Cloudstone Curio and Altar of the Brood each trigger twice.
7. Resolve both Altar of the Brood triggers, causing each opponent to mill two cards.
8. Resolve both Cloudstone Curio triggers, returning Estrid's Invocation and any other non-Saga enchantment from the battlefield to your hand.
9. Resolve the Estrid's Invocation trigger, putting it and the non-Saga enchantment onto the battlefield from your hand.
10. Repeat from step 5.