Remembrance + Mortuary + Phyrexian Walker + Yahenni, Undying Partisan

Remembrance

Mortuary

Phyrexian Walker

Yahenni, Undying Partisan

How it works

1. Activate Yahenni by sacrificing Phyrexian Walker.
2. When Phyrexian Walker dies, Mortuary and Remembrance trigger.
3. Resolve the Mortuary trigger, putting Phyrexian Walker from your graveyard on top of your library.
4. Resolve the Remembrance trigger, searching your library for Phyrexian Walker and putting it into your hand.
5. Resolve the Yahenni ability.
6. Cast Phyrexian Walker by paying 0.
7. Repeat.