Saffi Eriksdotter + Mistmoon Griffin + Yahenni, Undying Partisan

Saffi Eriksdotter

Mistmoon Griffin

Yahenni, Undying Partisan

How it works

1. Activate Saffi by sacrificing it, targeting Mistmoon Griffin.
2. Activate Yahenni by sacrificing Mistmoon Griffin.
3. When Mistmoon Griffin dies, it and Saffi trigger.
4. Resolve the Saffi trigger, returning Mistmoon Griffin from your graveyard to the battlefield.
5. Resolve the Mistmoon Griffin trigger, failing to exile it as it is not in your graveyard and then returning Saffi from your graveyard to the battlefield.
6. Resolve the Yahenni ability.
7. Repeat.