How can you create a combo with Yarok, the Desecrated, Gravebane Zombie, Bolas's Citadel, Verdant Sun's Avatar, Phyrexian Altar?
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[START OF COMBO]This combo can be formed with Yarok, the Desecrated, Gravebane Zombie, Bolas's Citadel, Verdant Sun's Avatar, Phyrexian Altar

Color identity: BGU
Mana cost: 
Steps:
  1. Activate Phyrexian Altar by sacrificing Gravebane Zombie, adding one mana of any color.
  2. Gavebane Zombie is put on top of your library instead of your graveyard.
  3. Cast Gravebane Zombie from the top of your library by paying four life.
  4. When Gravebane Zombie enters the battlefield, Verdant Sun's Avatar triggers twice, causing you to gain four life.
  5. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite colored mana
  - Infinite death triggers
  - Infinite enters the battlefield
  - Infinite lifegain triggers
  - Infinite leaves the battlefield
  - Infinite sacrifice triggers
  - Infinite storm count[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
  - Your life total is at least five.
[END OF COMBO PREREQUISITES]
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