Breach the Multiverse, Dualcaster Mage, and Yahenni, Undying Partisan

Prerequisites

• Breach the Multiverse in hand
• Dualcaster Mage in hand
• Yahenni, Undying Partisan on the battlefield
• available

Steps

1. Cast Breach the Multiverse by paying its mana cost, targeting any applicable target
2. Holding priority, cast Dualcaster Mage by paying its mana cost
3. When Dualcaster Mage enters, it triggers, targeting Breach the Multiverse
4. Holding priority, activate Yahenni by sacrificing Dualcaster Mage
5. Resolve the Dualcaster Mage trigger, copying Breach the Multiverse, with the copy targeting Dualcaster Mage Resolve the Breach the Multiverse copy, returning Dualcaster Mage from your graveyard to the battlefield
6. Repeat from step 3

Results

• Infinite LTB
• Infinite ETB
• Infinite sacrifice triggers
• Infinite death triggers
• Infinite mill
• Infinite self-mill
• Put all creature cards from your library onto the battlefield
• Infinite magecraft triggers
• Infinite recursion of creature cards in your graveyard
• Put all creature cards from each opponent's library onto the battlefield under your control