Cauldron of Souls, Corridor Monitor, Ridgescale Tusker, and Altar of Dementia

Prerequisites

• Cauldron of Souls on the battlefield
• Corridor Monitor on the battlefield
• Ridgescale Tusker on the battlefield
• Altar of Dementia on the battlefield

Steps

1. Activate Cauldron of Souls by tapping it, giving Ridgescale Tusker and Corridor Monitor persist until end of turn
2. Activate Altar of Dementia by sacrificing Corridor Monitor
3. Corridor Monitor dies, triggering its persist ability, returning itself from your graveyard to the battlefield with a -1/-1 counter on it
4. Corridor Monitor enters the battlefield, untapping Cauldron of Souls
5. Activate Altar of Dementia by sacrificing Ridgescale Tusker
6. Ridgescale Tusker dies, triggering its persist ability, returning itself from your graveyard to the battlefield with a -1/-1 counter on it
7. Ridgescale Tusker enters the battlefield, putting a +1/+1 counter on each creature you control
8. Resolve both Altar of Dementia abilities, causing target player to mill cards equal to Corridor Monitor and Ridgescale Tusker's power
9. Repeat

Results

• Infinite +1/+1 counters on all other creatures you control
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite mill
• Infinite sacrifice triggers
• Infinite self-mill