How can you create a combo with Bogbrew Witch, Festering Newt, Mortuary, Ashnod's Altar, Thornbite Staff?
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[START OF COMBO]This combo can be formed with Bogbrew Witch, Festering Newt, Mortuary, Ashnod's Altar, Thornbite Staff

Color identity: B
Mana cost: {2}
Steps:
  1. Activate Bogbrew Witch by paying {2} and tapping it, searching your library for Festering Newt and putting it onto the battlefield.
  2. Activate Ashnod's Altar by sacrificing Festering Newt, adding {C}{C}.
  3. When Festering Newt dies, it, Bogbrew Witch and Mortuary trigger.
  4. Resolve the Festering Newt trigger, giving any creature an opponent controls -4/-4 until end of turn.
  5. Resolve the Mortuary trigger, putting Festering Newt on top of your library from your graveyard.
  6. Resolve the Bogbrew Witch trigger, untapping it.
  7. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite death triggers
  - Infinite enters the battlefield
  - Infinite leaves the battlefield
  - Infinite sacrifice triggers
  - Reduce any number of opposing creatures' toughness to zero[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Bogbrew Witch must be on the battlefield
  - Festering Newt must be in the library
  - Mortuary must be on the battlefield
  - Ashnod's Altar must be on the battlefield
  - Thornbite Staff must be on the battlefield
  - Bogbrew Witch does not have summoning sickness.
  - Thornbite Staff attached to Bogbrew Witch.
[END OF COMBO PREREQUISITES]
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