Boonweaver Giant + Shade's Form + Yahenni, Undying Partisan

Boonweaver Giant

Shade's Form

Yahenni, Undying Partisan

How it works

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