Cultivator Colossus, Infinite Reflection, Mortuary, Nature's Revolt, and Altar of Dementia

Prerequisites

• Cultivator Colossus on the battlefield
• Infinite Reflection on the battlefield
• Mortuary on the battlefield
• Nature's Revolt on the battlefield
• Altar of Dementia on the battlefield
• You have at least two land cards in hand
• Infinite Reflection attached to Cultivator Colossus

Steps

1. Play any land from your hand
2. The land enters the battlefield as a copy of Cultivator Colossus due to Nature's Revolt and Infinite Reflection
3. When the land enters the battlefield, it triggers
4. Holding priority, activate Altar of Dementia by sacrificing the land
5. When the land dies, Mortuary triggers, putting the land on top of your library from your graveyard
6. Resolve the Altar of Dementia ability, causing target opponent to mill cards equal to the land's power
7. Resolve the land's trigger from step 3, causing you to put any other land onto the battlefield from your hand, draw a card, and then decline to put another land onto the battlefield
8. Repeat from step 2

Results

• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite mill
• Infinite sacrifice triggers