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Phyrexian Tower combines a land slot with a sacrifice outlet and a burst of black mana. Its normal tap ability supplies colorless. The second ability taps the land and sacrifices a creature to add two black mana, letting an expendable body help pay for interaction, recursion, or a larger black spell.
Ophiomancer’s Snake tokens can provide material, while Blood Artist rewards the death. Sacrificing a creature in response to targeted exile can preserve a death trigger or put the creature into a graveyard where recursion can reach it. Tower must be untapped to perform that job, and it cannot keep sacrificing creatures without another way to untap the land.
A productive sacrifice deck needs a supply of bodies, a reason to let them die, and a way to turn that exchange into progress. Recurring creatures and token makers provide material, while effects such as Blood Artist can add pressure to deaths that already serve another purpose. Count each return cost and mana payment before treating a sequence as a repeatable combo.
Leaving Tower untapped can represent both mana and a sacrifice opportunity. That matters when an opponent tries to steal an important creature or exile a recursion target. The second ability sacrifices as a cost, so the creature is already gone before anyone can respond to the resulting death triggers.
