How can you create a combo with Galadriel of Lothlórien, Dryad Arbor, Retreat to Coralhelm, Mortuary, Altar of Dementia?
user
[START OF COMBO]This combo can be formed with Galadriel of Lothlórien, Dryad Arbor, Retreat to Coralhelm, Mortuary, Altar of Dementia

Color identity: BGU
Mana cost: 
Steps:
  1. Play Dryad Arbor.
  2. When Dryad Arbor enters the battlefield, Retreat to Coralhelm triggers.
  3. Holding priority, activate Altar of Dementia by sacrificing Dryad Arbor.
  4. When Dryad Arbor dies, Mortuary triggers, putting Dryad Arbor on top of your library from your graveyard.
  5. Resolve the Altar of Dementia ability, causing target player to mill cards equal to Dryad Arbor's power.
  6. Resolve the Retreat to Coralhelm trigger from step 2, causing you to scry 1, ensuring to leave Dryad Arbor on top of your library.
  7. Galadriel's second ability triggers, causing you to reveal Dryad Arbor from the top of your library, and put it onto the battlefield tapped.
  8. Repeat from step 2.[END OF COMBO STEPS]

Result:
  - Infinite death triggers
  - Infinite enters the battlefield
  - Infinite landfall triggers
  - Infinite leaves the battlefield
  - Infinite mill
  - Infinite sacrifice triggers
  - Infinite self-mill[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Galadriel of Lothlórien must be on the battlefield
  - Dryad Arbor must be in your hand
  - Retreat to Coralhelm must be on the battlefield
  - Mortuary must be on the battlefield
  - Altar of Dementia must be on the battlefield
  - You are abile to play a land this turn.
[END OF COMBO PREREQUISITES]
assistant