You control at least one additional nontoken non-Human creature with toughness two or greater.
Steps
Activate
Yawgmoth by paying 1 life and sacrificing Gray Merchant, targeting any other nontoken non-Human creature you control.
Gray Merchant dies, triggering its undying ability, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
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.
Resolve the
Yawgmoth ability from step 1, putting a -1/-1 counter on the additional creature and causing you to draw a card.
Activate
Yawgmoth by paying 1 life and sacrificing the additional creature, targeting Gray Merchant.
The creature dies, triggering its undying ability, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
Resolve the
Yawgmoth ability, putting a -1/-1 counter on Gray Merchant and causing you to draw a card.
Repeat.
Results
Infinite card draw.
Infinite draw triggers.
Near-infinite death triggers.
Near-infinite creature ETB.
Near-infinite lifegain.
Near-infinite lifegain triggers.
Near-infinite lifeloss.
Near-infinite creature LTB.
Near-infinite creature sacrifice triggers.
Metadata
Bracket tag
ExhibitionBracket 1+
For any deck
1
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5
1 · Exhibition5 · cEDH
Bracket tags are estimated from the cards and results of each combo, as a guideline rather than a strict classification.