How can you create a combo with Dreams of the Dead, Void Maw, Priest of Gix, Phyrexian Altar?
user
[START OF COMBO]This combo can be formed with Dreams of the Dead, Void Maw, Priest of Gix, Phyrexian Altar

Color identity: UB
Mana cost: 
Steps:
  1. Activate Phyrexian Altar by sacrificing Priest of Gix, adding {U} and exiling it to Void Maw.
  2. Activate Void Maw by returning Priest of Gix to your graveyard, giving Void Maw +2/+2 until end of turn.
  3. Activate Dreams of the Dead for {1}{U}, returning Priest of Gix from your graveyard to the battlefield.
  4. When Priest of Gix ETBs, add {B}{B}{B}.
  5. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite black mana
  - Infinite death triggers
  - Infinite enters the battlefield
  - Infinite leaves the battlefield
  - Infinitely large Void Maw until end of turn
  - Infinite sacrifice triggers[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
[END OF COMBO PREREQUISITES]
assistant