Phenax, God of Deception, and Eater of the Dead

Prerequisites

• Phenax, God of Deception on the battlefield
• Eater of the Dead on the battlefield

Steps

1. Tap Eater using the obtained activated ability from Phenax, milling your opponent for 4 cards
2. If, after the mill, a creature card exists in any graveyard, pay and exile a creature card from a graveyard for Eater's activated ability to untap it
3. Repeat until you've milled out your opponent or run out of creature cards in graveyards to exile

Results

• Mills your opponents' libraries out
• The combo depends on the number of creature cards in your opponents' collective graveyards