How can you create a combo with Encroaching Mycosynth, Dualcaster Mage, Scrap Mastery, Altar of Dementia?
user
[START OF COMBO]This combo can be formed with Encroaching Mycosynth, Dualcaster Mage, Scrap Mastery, Altar of Dementia

Color identity: UR
Mana cost: {4}{R}{R}{R}{R}
Steps:
  1. Cast Scrap Mastery by paying {3}{R}{R}.
  2. In response, cast Dualcaster Mage by paying {1}{R}{R}.
  3. Dualcaster Mage enters the battlefield, copying Scrap Mastery.
  4. Activate Altar of Dementia by sacrificing Dualcaster Mage, causing any player to mill two cards.
  5. Resolve a copy of Scrap Mastery, swapping all nonland permanents you control with all nonland permanents in your graveyard.
  6. Repeat from step 3.[END OF COMBO STEPS]

Result:
  - Infinite blinking of nonland permanents in graveyard or library or on the battlefield
  - Infinite death triggers
  - Infinite enters the battlefield
  - Infinite leaves the battlefield
  - Infinite magecraft triggers
  - Infinite mill
  - Infinite sacrifice triggers
  - Infinite self-mill[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Encroaching Mycosynth must be on the battlefield
  - Dualcaster Mage must be in your hand
  - Scrap Mastery must be in your hand
  - Altar of Dementia must be on the battlefield
[END OF COMBO PREREQUISITES]
assistant