Agatha's Soul Cauldron, Deeproot Pilgrimage, and Vizier of Tumbling Sands

Prerequisites

• Agatha's Soul Cauldron on the battlefield
• Deeproot Pilgrimage on the battlefield
• Vizier of Tumbling Sands in exile

Steps

1. Activate the nontoken Merfolk using Vizier of Tumbling Sands's ability by tapping it
2. Deeproot Pilgrimage triggers, creating a 1/1 Merfolk creature token
3. Resolve the Merfolk's ability, untapping the other creature
4. Activate the other creature using Vizier of Tumbling Sands's ability by tapping it, untapping the nontoken Merfolk
5. Repeat

Results

• Infinite ETB
• Infinite creature tokens