Solemnity, and Shilgengar, Sire of Famine

Prerequisites

• Solemnity on the battlefield
• Shilgengar, Sire of Famine on the battlefield
• If a persist creature is used, it does not have a -1/-1 counter on it
• Otherwise, if an undying creature is used, it does not have a +1/+1 counter on it

Steps

1. Activate Shilgengar by sacrificing the persist or undying creature
2. When the creature dies, its persist or undying ability triggers, returning it from your graveyard to the battlefield without a -1/-1 counter or a +1/+1 counter on it due to Solemnity
3. Resolve the Shilgengar ability
4. Repeat

Results

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