Veinwitch Coven + Phyrexian Altar + Vein Ripper

Veinwitch Coven

Phyrexian Altar

Vein Ripper

How it works

1. Activate Phyrexian Altar by sacrificing the one-drop creature, adding .
2. When that creature dies, it and Vein Ripper trigger.
3. Resolve the creature's ability, creating a creature token.
4. Resolve the Vein Ripper ability, gaining at least one life and causing at least one opponent to lose at least one life.
5. When you gain life, Veinwitch Coven triggers, causing you to pay to return the one-drop creature from your graveyard to your hand.
6. Activate Phyrexian Altar by sacrificing the token creature, adding one colored mana.
7. Cast the creature by paying one mana.
8. Repeat.