Yawgmoth by paying 1 life and sacrificing a creature, targeting any creature an opponent controls.
When the sacrificed creature dies,
Grave Venerations triggers, causing you to gain 1 life and each opponent to lose 1 life.
Resolve the
Yawgmoth ability, putting a -1/-1 counter on a creature an opponent controls, and causing you to draw a card.
Nest of Scarabs triggers, creating a creature token.
Repeat.
Notes
You may also repeat this loop whenever a creature enters the battlefield under an opponent's control. The lock will end once you've drawn your library.
Results
Destroy all creatures opponents control.
Destroy each creature that enters the battlefield under an opponent's control.
Near-infinite -1/-1 counters.
Near-infinite card draw.
Near-infinite creature ETB.
Near-infinite creature LTB.
Near-infinite creature sacrifice triggers.
Near-infinite death triggers.
Near-infinite draw triggers.
Near-infinite lifegain triggers.
Near-infinite lifeloss.
Metadata
Lock
Bracket tag
SpicyBracket 3-4+
Probably 3 or 4, but hard to classify
1
2
3
4
5
1 · Exhibition5 · cEDH
Bracket tags are estimated from the cards and results of each combo, as a guideline rather than a strict classification.