Reassembling Skeleton + Phyrexian Altar + Sifter of Skulls

Reassembling Skeleton

Phyrexian Altar

Sifter of Skulls

How it works

1. Activate Phyrexian Altar by sacrificing Reassembling Skeleton, adding
2. Sifter of Skulls triggers, creating a 1/1 Eldrazi Scion creature token with "Sacrifice this creature: add C"
3. Activate the Eldrazi Scion by sacrificing it, adding C.
4. Activate Reassembling Skeleton by paying 1, returning it from your graveyard to the battlefield tapped.
5. Repeat.

This elegant loop turns the tireless persistence of Reassembling Skeleton into a self-sustaining engine of sacrifice. By feeding the Skeleton directly to Phyrexian Altar, you generate the black mana needed to pay its activation cost, while the presence of Sifter of Skulls ensures that every death yields an Eldrazi Scion token to cover the remaining colorless mana. Because Phyrexian Altar can convert that generated Scion mana into the exact color required, the cycle closes seamlessly to generate infinite deaths and sacrifices at will.