How can you create a combo with Gravespawn Sovereign, Intruder Alarm, Ashnod's Altar?
user
[START OF COMBO]This combo can be formed with Gravespawn Sovereign, Intruder Alarm, Ashnod's Altar

Color identity: UB
Mana cost: 
Steps:
  1. Activate Ashnod's Altar by sacrificing a nontoken creature, adding {C}{C}.
  2. Activate Gravespawn Sovereign by tapping five untapped Zombies you control, returning any creature from your graveyard to the battlefield.
  3. The creature enters the battlefield, triggering Intruder Alarm, untapping all creatures.
  4. Repeat.[END OF COMBO STEPS]

Result:
  - Infinite colorless mana
  - Infinite death triggers
  - Infinite enters the battlefield
  - Infinite leaves the battlefield
  - Infinite sacrifice triggers
  - Infinite untap of creatures[END OF COMBO RESULT][END OF COMBO]

Other prerequisites:
  - All permanants must be on the battlefield
  - You control at least four other Zombies and an additional nontoken creature.
[END OF COMBO PREREQUISITES]
assistant