Haru, Hidden Talent, Bloodghast, Altar of Dementia, and Rukarumel, Biologist

Prerequisites

• Haru, Hidden Talent on the battlefield
• Bloodghast in hand
• Altar of Dementia on the battlefield
• Rukarumel, Biologist on the battlefield
• available

Steps

1. Cast Bloodghast by paying
2. When Bloodghast enters as an Ally due to Rukarumel, Haru triggers, earthbending a land
3. Activate Altar of Dementia by sacrificing Bloodghast
4. Activate Altar of Dementia by sacrificing a land creature
5. When the land creature dies, Haru triggers, returning the land from your graveyard to the battlefield
6. When the land enters, Bloodghast triggers, returning itself from your graveyard to the battlefield
7. When Bloodghast enters as an Ally due to Rukarumel, Haru triggers, earthbending a land
8. Resolve the Altar of Dementia ability from step 4
9. Repeat from step 3

Results

• Infinite LTB
• Infinite ETB
• Infinite sacrifice triggers
• Infinite death triggers
• Infinite mill
• Infinite self-mill
• Infinite landfall triggers
• Infinite mana lands you control that enter the battlefield untapped can produce