Altar of Dementia, Watcher of the Roost, and Yedora, Grave Gardener

Prerequisites

• Altar of Dementia on the battlefield
• Watcher of the Roost on the battlefield
• Yedora, Grave Gardener on the battlefield
• You have at least one white card in hand

Steps

1. Activate Altar of Dementia by sacrificing Watcher of the Roost
2. When Watcher of the Roost dies, Yedora triggers, returning Watcher of the Roost from your graveyard to the battlefield face down as a Forest land
3. Resolve the Altar of Dementia ability, causing target player to mill cards equal to Watcher of the Roost's power
4. Activate Watcher of the Roost by tapping it, adding
5. Activate Watcher of the Roost's morph ability by revealing a white card from your hand, turning it face up
6. Watcher of the Roost triggers, causing you to gain 2 life
7. Repeat

Results

• Infinite death triggers
• Infinite green mana
• Infinite landfall triggers
• Infinite lifegain
• Infinite lifegain triggers
• Infinite LTB
• Infinite mill
• Infinite sacrifice triggers
• Infinite self-mill