Korozda Gorgon, and Ashnod's Altar

Prerequisites

• Korozda Gorgon on the battlefield
• Ashnod's Altar on the battlefield
• undefined

Steps

1. Activate Ashnod's Altar by sacrificing the undying creature, adding
2. When the undying creature dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it
3. Activate Korozda Gorgon by paying and removing the +1/+1 counter from the undying creature, targeting any creature
4. Holding priority, repeat from step 1
5. Resolve all Korozda Gorgon abilities

Results

• Infinite LTB
• Infinite ETB
• Infinite sacrifice triggers
• Infinite death triggers
• Reduce any number of target creatures' toughness to 0