How can you create a combo with Bolas's Citadel, Beacon of Immortality, Phyrexian Devourer?
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[START OF COMBO]This combo can be formed with Bolas's Citadel, Beacon of Immortality, Phyrexian Devourer

Color identity: WB
Mana cost: {5}{W}
Steps:
  1. Activate Phyrexian Devourer repeatedly while holding priority by exiling your library.
  2. Cast Beacon of Immortality by paying {5}{W}, doubling your life total and shuffling Beacon of Immortality into your empty library.
  3. Cast Beacon of Immortality from the top of your library by paying 6 life, doubling your life total and shuffling Beacon of Immortality into your empty library.
  4. Repeat any number of times.
  5. Resolve all remaining Phyrexian Devourer abilities and resulting Phyrexian Devourer triggered abilities, sacrificing Phyrexian Devoruer.
  6. If you have at least 7 life, this combo results in infinite lifegain.[END OF COMBO STEPS]

Result:
  - Exile your library
  - Infinite lifegain
  - Infinite lifegain triggers
  - Infinite magecraft triggers
  - Infinite storm count[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - Bolas's Citadel must be on the battlefield
  - Beacon of Immortality must be in your hand or in the library
  - Phyrexian Devourer must be on the battlefield
  - You have at least 6 life.
  - Note that mana and life prerequisite are different if Beacon of Immortality starts on top of your library.
[END OF COMBO PREREQUISITES]
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