Dual Nature, Balthor the Defiled, and Blood Vassal

Prerequisites

• Dual Nature on the battlefield
• Balthor the Defiled on the battlefield
• Blood Vassal on the battlefield
• Balthor in hand
• available

Steps

1. Cast Balthor by paying
2. Balthor enters the battlefield, triggering Dual Nature's first ability, creating a token copy of Balthor
3. Put the nontoken Balthor into your graveyard due to the legend rule
4. Activate Blood Vassal by sacrificing it, adding
5. Activate the token Balthor by paying and exiling it, returning all black and red creature cards from your graveyard to the battlefield
6. Balthor and Blood Vassal enter the battlefield, triggering Dual Nature's first ability twice
7. Resolve the first Dual Nature trigger, creating a token copy of Blood Vassal
8. Activate the token Blood Vassal by sacrificing it, adding
9. Resolve the second Dual Nature trigger, creating a token copy of Balthor
10. Repeat from step 3

Results

• Infinite black mana
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers