Phyrexian Altar, Dualcaster Mage, and Dread Return

Prerequisites

• Phyrexian Altar on the battlefield
• Dualcaster Mage in hand
• Dread Return in hand
• available

Steps

1. Cast Dread Return by paying its mana cost Holding priority, cast Dualcaster Mage by paying its mana cost
2. When Dualcaster Mage enters, it triggers, targeting Dread Return
3. Holding priority, activate Phyrexian Altar by sacrificing Dualcaster Mage
4. Resolve the Dualcaster Mage trigger, copying Dread Return Resolve the Dread Return copy, returning Dualcaster Mage from your graveyard to the battlefield
5. Repeat from step 3

Results

• Infinite ETB
• Infinite LTB
• Infinite colored mana
• Infinite death triggers
• Infinite magecraft triggers
• Infinite sacrifice triggers