Danitha, Benalia's Hope + Shade's Form + Yahenni, Undying Partisan

Danitha, Benalia's Hope

Shade's Form

Yahenni, Undying Partisan

How it works

1. Activate Yahenni by sacrificing Danitha.
2. When Danitha dies, Shade's Form triggers, returning Danitha from your graveyard to the battlefield tapped.
3. When Danitha enters the battlefield, it triggers, returning Shade's Form from your graveyard to the battlefield attached to Danitha.
4. Resolve the Yahenni ability.
5. Repeat.