Altar of Dementia + Siona, Captain of the Pyleas Combos

3 known combos featuring both cards in Commander

Infinite death triggers Infinite ETB Infinite LTB Infinite mill Infinite sacrifice triggers

Combo 1 with Reins of the Vinesteed

Results: Infinite death triggers · Infinite ETB · Infinite LTB · Infinite mill · Infinite sacrifice triggers · Infinite self-mill
Steps
  1. Cast Reins of the Vinesteed by paying {3}{G}, enchanting any Human or Soldier you control besides Siona.
  2. Siona triggers, creating a 1/1 Human Soldier creature token.
  3. Activate Altar of Dementia by sacrificing the creature enchanted by Reins of the Vinesteed.
  4. The creature dies, triggering Reins of the Vinesteed, returning Reins of the Vinesteed to the battlefield enchanting the Human Soldier token.
  5. Siona triggers, creating a 1/1 Human Soldier creature token.
  6. Resolve the Altar of Dementia ability, causing target player to mill cards equal to the sacrificed creature's power.
  7. Repeat from step 3.

Combo 2 with Traveling Plague

Also requires: Traveling Plague Traveling Plague
Results: Infinite ETB · Infinite LTB · Infinite death triggers · Infinite mill · Infinite sacrifice triggers · Infinite self-mill
Show steps
  1. Cast Traveling Plague by paying {3}{B}{B}, attaching it to another creature you control.
  2. When Traveling Plague enters, Siona triggers, creating a creature token.
  3. Activate Altar of Dementia by sacrificing the creature Traveling Plague is attached to.
  4. When the creature dies, Traveling Plague triggers, returning itself from your graveyard to the battlefield attached to the token created in step 2.
  5. When Traveling Plague enters, Siona triggers, creating a creature token.
  6. Resolve the Altar of Dementia ability.
  7. Repeat from step 3.

Combo 3 with Cass, Hand of Vengeance

Results: Infinite ETB · Infinite LTB · Infinite death triggers · Infinite mill · Infinite sacrifice triggers · Infinite self-mill
Show steps
  1. Activate Altar of Dementia by sacrificing another creature that has an Aura attached to it.
  2. When the creature dies, Cass triggers, returning an Aura that was attached to the creature from your graveyard to the battlefield attached to another creature you control.
  3. When the Aura enters the battlefield, Siona triggers, creating a creature token.
  4. Resolve the Altar of Dementia ability.
  5. Repeat.
📚 Learn more:
Buy Altar of Dementia on TCGPlayer Buy on Amazon

As an Amazon Associate and TCGPlayer affiliate I earn from qualifying purchases.

Buy Siona, Captain of the Pyleas on TCGPlayer Buy on Amazon

As an Amazon Associate and TCGPlayer affiliate I earn from qualifying purchases.