Shilgengar, Sire of Famine, Putrid Goblin, and Thran Vigil

Prerequisites

• Shilgengar, Sire of Famine on the battlefield
• Putrid Goblin on the battlefield
• Thran Vigil on the battlefield

Steps

1. Activate Shilgengar by sacrificing Putrid Goblin
2. When Putrid Goblin dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it
3. Thran Vigil triggers, putting a +1/+1 counter on Putrid Goblin
4. Resolve the Shilgengar ability
5. Repeat

Results

• Infinite Blood tokens
• Infinite ETB
• Infinite LTB
• Infinite death triggers
• Infinite sacrifice triggers