Preston, the Vanisher + Phyrexian Altar + Karmic Guide + Chord of Calling

Preston, the Vanisher

Phyrexian Altar

Karmic Guide

Chord of Calling

How it works

1. Cast Chord of Calling by paying at most 5, searching your library for Karmic Guide and putting it onto the battlefield.
2. When Karmic Guide enters, it and Preston trigger.
3. Resolve the Karmic Guide trigger, returning an applicable target from your graveyard to the battlefield.
4. Holding priority, activate Phyrexian Altar by sacrificing Karmic Guide.
5. Resolve the Preston trigger, creating a token copy of Karmic Guide that is a 0/1 Illusion.
6. When the Karmic Guide token enters, it triggers, returning Karmic Guide from your graveyard to the battlefield.
7. Repeat from step 2.