Laboratory Maniac, and Phyrexian Devourer

Prerequisites

• Laboratory Maniac on the battlefield
• Phyrexian Devourer on the battlefield
• You have a way to draw a card

Steps

1. Activate Phyrexian Devourer by exiling the top card of your library
2. Repeat step 1 until you have an empty library
3. Resolve a Phyrexian Devourer ability, putting a number of +1/+1 counters on it equal to the exiled card's mana value
4. If Phyrexian Devourer has a power of at least seven, it triggers, causing you to sacrifice it
5. Repeat steps 3-4 until you sacrifice Phyrexian Devourer, thus causing all remaining Phyrexian Devourer abilities to fail to resolve due to having no legal targets
6. Draw a card, causing you to win the game due to drawing from an empty library

Results

• Exile your library
• Win the game