Altar of Dementia, Hardened Academic, and Obstinate Gargoyle

Prerequisites

• Altar of Dementia on the battlefield
• Hardened Academic on the battlefield
• Obstinate Gargoyle on the battlefield

Steps

1. Activate Altar of Dementia by sacrificing Obstinate Gargoyle
2. When Obstinate Gargoyle dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it
3. Hardened Academic triggers, putting a +1/+1 counter on Obstinate Gargoyle
4. Resolve the Altar of Dementia ability
5. Repeat

Results

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