Young Necromancer + Altar of Dementia

Young Necromancer
Altar of Dementia

Requires
Young Necromancer must be in hand. Altar of Dementia must be on the battlefield. Mana needed: 4b
Steps
  1. Cast Young Necromancer by paying 4b.
  2. Young Necromancer enters the battlefield, triggering its ability.
  3. Holding priority, activate Altar of Dementia by sacrificing Young Necromancer, causing you to mill two cards.
  4. Resolve the Young Necromancer trigger, exiling two cards from your graveyard except Young Necromancer, and returning Young Necromancer from your graveyard to the battlefield.
  5. Repeat from step 2.
Results
Infinite self-mill. Near-infinite death triggers. Near-infinite ETB. Near-infinite LTB. Near-infinite sacrifice triggers.