How can you create a combo with Mikaeus, the Unhallowed, Yawgmoth, Thran Physician, Gray Merchant of Asphodel?
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[START OF COMBO]This combo can be formed with Mikaeus, the Unhallowed, Yawgmoth, Thran Physician, Gray Merchant of Asphodel

Color identity: B
Mana cost: 
Steps:
  1. Activate Yawgmoth by paying 1 life and sacrificing Gray Merchant, targeting any other nontoken non-Human creature you control.
  2. Gray Merchant dies, triggering its undying ability, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
  3. Gray Merchant enters the battlefield, causing each opponent to lose life equal to your devotion to black, and causing you to gain life equal to the life lost this way.
  4. Resolve the Yawgmoth ability from step 1, putting a -1/-1 counter on the additional creature and causing you to draw a card.
  5. Activate Yawgmoth by paying 1 life and sacrificing the additional creature, targeting Gray Merchant.
  6. The creature dies, triggering its undying ability, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
  7. Resolve the Yawgmoth ability, putting a -1/-1 counter on Gray Merchant and causing you to draw a card.
  8. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite card draw
  - Infinite draw triggers
  - Near-infinite death triggers
  - Near-infinite enters the battlefield
  - Near-infinite lifegain
  - Near-infinite lifegain triggers
  - Near-infinite lifeloss
  - Near-infinite leaves the battlefield
  - Near-infinite sacrifice triggers[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
  - Your life total is at least 2.
  - You control at least one additional nontoken non-Human creature with toughness two or greater.
[END OF COMBO PREREQUISITES]
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