Feign Death, Dualcaster Mage, and Ashnod's Altar

Prerequisites

• Feign Death in hand
• Dualcaster Mage in hand
• Ashnod's Altar on the battlefield
• available

Steps

1. Cast Feign Death by paying , targeting any creature
2. Holding priority, cast Dualcaster Mage by paying
3. Dualcaster Mage enters the battlefield, creating a copy of Feign Death, targeting Dualcaster Mage
4. Resolve the copy of Feign Death, causing Dualcaster Mage to return to the battlefield tapped and with a +1/+1 counter on it when it dies this turn
5. Activate Ashnod's Altar by sacrificing Dualcaster Mage, adding
6. Dualcaster Mage triggers, returning itself to the battlefield tapped with a +1/+1 counter on it
7. Repeat from step 3

Results

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