Nim Deathmantle + Ashnod's Altar + Ashaya, Soul of the Wild + Omnath, Locus of Rage

Nim Deathmantle

Ashnod's Altar

Ashaya, Soul of the Wild

Omnath, Locus of Rage

How it works

1. Activate Ashnod's Altar by sacrificing Ashaya, adding CC.
2. When Ashaya dies, Nim Deathmantle and Omanth's second ability trigger.
3. Resolve the Omnath trigger, dealing 3 damage to any target.
4. Resolve the Nim Deathmantle trigger, causing you to pay 4 to return Ashaya from your graveyard to the battlefield, and attaching Nim Deathmantle to it.
5. When Ashaya enters the battlefield, Omnath's first and second abilities trigger.
6. Resolve the first Omnath trigger, creating a 5/5 Elemental creature token.
7. Resolve the second Omnath trigger, dealing 3 damage to any target.
8. Activate Ashnod's Altar by sacrificing the Elemental token, adding CC.
9. When the Elemental dies, Omanth's second ability triggers, dealing 3 damage to any target.
10. Repeat.
11. If you control a nontoken creature that has haste, you may instead sacrifice it, and then tap it each iteration to get infinite green mana and colorless mana.