Rowan, Scion of War, Debt to the Deathless, and Necropotence

Prerequisites

• Rowan, Scion of War on the battlefield
• Debt to the Deathless in hand
• Necropotence on the battlefield
• Your life total is equal to or greater than half the highest life total among your opponents, rounded up
• Rowan does not have summoning sickness
• available

Steps

1. Activate Necropotence by paying 1 life, exiling the top card of your library
2. Repeat step 1 until you have paid an amount of life equal to half the highest life total among your opponents, rounded up
3. Activate Rowan by tapping it, reducing the cost of all black and/or red spells you cast this turn
4. Cast Debt to the Deathless, choosing for X to equal the amount of life you've lost this turn, but paying a total of due to Rowan's ability
5. Resolve Debt to the Deathless, causing each opponent to lose twice X life, and you to gain life equal to the life lost this way
6. Each opponent loses the game due to having 0 or less life

Results

• Each opponent loses the game
• Near-infinite lifegain
• Near-infinite lifeloss