Stalwart Successor, Puppeteer Clique, and Yahenni, Undying Partisan

Prerequisites

• Stalwart Successor on the battlefield
• Puppeteer Clique on the battlefield
• Yahenni, Undying Partisan on the battlefield

Steps

1. Activate Yahenni by sacrificing Puppeteer Clique When Puppeteer Clique dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it
2. When Puppeteer Clique enters, it and Stalwart Successor trigger
3. Resolve the Puppeteer Clique trigger, putting a creature from an opponent's graveyard onto the battlefield under your control
4. Resolve the Stalwart Successor trigger, putting a +1/+1 counter on Puppeteer Clique Resolve the Yahenni ability
5. Repeat

Results

• Infinite ETB
• Infinite LTB
• Infinite death triggers
• Infinite sacrifice triggers
• Put all creature cards from each opponent's graveyard onto the battlefield under your control