Preston, the Vanisher + Sister Hospitaller + Umbral Collar Zealot + Nature's Rhythm

Preston, the Vanisher

Sister Hospitaller

Umbral Collar Zealot

Nature's Rhythm

How it works

1. Cast Nature's Rhythm from your hand by paying 6 or from your graveyard for its harmonize cost by paying at most 6, searching your library for Sister Hospitaller and putting it onto the battlefield.
2. When Sister Hospitaller enters, it and Preston trigger.
3. Resolve the Sister Hospitaller trigger, returning an applicable target from your graveyard to the battlefield.
4. Holding priority, activate Umbral Collar Zealot by sacrificing Sister Hospitaller.
5. Resolve the Preston trigger, creating a token copy of Sister Hospitaller that is a 0/1 Illusion.
6. When the Sister Hospitaller token enters, it triggers, returning Sister Hospitaller from your graveyard to the battlefield.
7. Repeat from step 2.