Chthonian Nightmare + Eternal Witness + Temporal Manipulation

Chthonian Nightmare

Eternal Witness

Temporal Manipulation

How it works

1. Cast Temporal Manipulation by paying 3, causing you to take an extra turn after this one.
2. Move to your next turn.
3. Cast Chthonian Nightmare by paying 1.
4. When Chthonian Nightmare enters the battlefield, it triggers, causing you to get EEE.
5. Activate Chthonian Nightmare by paying EEE, sacrificing a creature with mana value 3 or less, and returning Chthonian Nightmare from the battlefield to your hand, returning Eternal Witness from your graveyard to the battlefield.
6. When Eternal Witness enters the battlefield, it triggers, returning Temporal Manipulation from your graveyard to your hand.
7. Cast Chthonian Nightmare by paying 1.
8. When Chthonian Nightmare enters the battlefield, it triggers, causing you to get EEE.
9. Activate Chthonian Nightmare by paying at most EEE, sacrificing Eternal Witness, and returning Chthonian Nightmare from the battlefield to your hand, returning a creature with mana value 3 or less from your graveyard to the battlefield.
10. Repeat.