Requires

Dual Nature must be on the battlefield. Sylvan Hierophant must be in hand. Phyrexian Altar must be on the battlefield. Mana needed:

Steps

1. Cast Sylvan Hierophant by paying .
2. Dual Nature's first ability triggers, creating a token copy of Sylvan Hierophant.
3. Sacrifice the nontoken Sylvan Hierophant to Phyrexian Altar, adding .
4. Dual Nature's second ability triggers, and Sylvan Hierophant triggers targeting any other creature card in your graveyard.
5. In response, sacrifice the token Sylvan Hierophant to Phyrexian Altar for .
6. Dual Nature's second ability triggers, and the Sylvan Hierophant token triggers.
7. Resolve the Sylvan Hierophant token's trigger, returning the nontoken Sylvan Hierophant to your hand.
8. Resolve both Dual Nature abilities, exiling zero creauters.
9. Resolve the nontoken Sylvan Hierophant's trigger, returning a creature card from your graveyard to your hand.
10. Repeat.

Results