The Master, Formed Anew, Cavalier of Night, and Altar of Dementia

Prerequisites

• The Master, Formed Anew on the battlefield
• Cavalier of Night in exile
• Altar of Dementia on the battlefield
• Cavalier of Night in exile with a takeover counter on it
• The Master on the battlefield as a copy of Cavalier of Night
• available

Steps

1. Activate Altar of Dementia by sacrificing The Master
2. When The Master dies, its second ability triggers, returning itself from your graveyard to the battlefield as a copy of Cavalier of Night
3. When The Master enters the battlefield, its first ability triggers, doing nothing
4. Resolve the Altar of Dementia ability, causing target player to mill cards equal to The Master's power
5. Repeat

Results

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