Umbral Collar Zealot + Dualcaster Mage + Leonardo's Technique

Prerequisites

• You have a creature card in your graveyard.

Steps

1. 1Cast Leonardo's Technique by paying its mana cost, targeting any applicable target.
2. 2Holding priority, cast Dualcaster Mage by paying its mana cost.
3. 3When Dualcaster Mage enters, it triggers, targeting Leonardo's Technique.
4. 4Holding priority, activate Umbral Collar Zealot by sacrificing Dualcaster Mage.
5. 5Resolve the Dualcaster Mage trigger, copying Leonardo's Technique, with the copy targeting Dualcaster Mage
6. 6Resolve the Leonardo's Technique copy, returning Dualcaster Mage from your graveyard to the battlefield.
7. 7Repeat from step 3.

Effects

• Infinite creature ETB
• Infinite creature LTB
• Infinite creature sacrifice triggers
• Infinite death triggers
• Infinite magecraft triggers
• Infinite recursion of creature cards in your graveyard
• Infinite surveil