Altar of Dementia + Haunted One + Intruder Alarm + Xavier Sal, Infested Captain

BGU identity

Commander legal

The 4 combo pieces

What must be in place

There is at least one counter on a permanent you control except Xavier Sal.
Xavier Sal does not have summoning sickness.
You control at least one additional nontoken Human, Fungus and/or Pirate that has no more than one +1/+1 counter on it.

How to execute it

  1. Activate Xavier Sal's first ability by tapping it and removing a +1/+1 counter from the additional nontoken Human, Fungus and/or Pirate if it has one, or any counter from another permanent you control otherwise.
  2. Xavier Sal triggers, causing it and all other creatures you control that share a creature type with it to get +2/+0 and gain undying until end of turn.
  3. Resolve the Xavier Sal ability, causing you to populate.
  4. Activate Altar of Dementia by sacrificing the additional Human, Fungus and/or Pirate.
  5. When the creature dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
  6. When the creature enters the battlefield, Intruder Alarm triggers, untapping all creatures.
  7. Resolve the Altar of Dementia ability, causing target player to mill cards equal to the sacrificed creature's power.
  8. Repeat.

What the combo produces