Emmara, Soul of the Accord, Ashnod's Altar, Earthcraft, and Umbral Mantle

Prerequisites

• Emmara, Soul of the Accord on the battlefield
• Ashnod's Altar on the battlefield
• Earthcraft on the battlefield
• Umbral Mantle on the battlefield
• Umbral Mantle attached to Emmara, Soul of the Accord
• At least 1 basic land under your control

Steps

1. Activate Earthcraft to tap Emmara, Soul of the Accord and untap a basic land
2. Tap the land for mana
3. Emmara, Soul of the Accord triggers creating a token creature
4. Activate Earthcraft to tap the token creature to untap a basic land
5. Tap the land for mana
6. Sacrifice the token creature to Ashnod's Altar floating
7. Activate Umbral Mantle to untap Emmara, Soul of the Accord
8. Repeat

Results

• Infinite colored mana
• Infinite colorless mana
• Infinite ETB
• Infinite LTB
• Infinitely large Emmara
• Infinite sacrifice triggers
• Infinite tokens