How can you create a combo with Intruder Alarm, Hell's Caretaker?
user
[START OF COMBO]This combo can be formed with Intruder Alarm, Hell's Caretaker

Color identity: UB
Mana cost: 
Steps:
  1. Tap Hell's Caretaker and sacrifice another creature to returning a creature in your graveyard to the battlefield.
  2. When that creature enters the battlefield, Intruder Alarm triggers untapping all creatures.
  3. Repeat.[END OF COMBO STEPS]

Result:
  - 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
  - Hell's Caretaker does not have summoning sickness.
  - It is your upkeep step.
  - You have at least one creature card in your graveyard and at least one additional nontoken creature on the battlefield.
[END OF COMBO PREREQUISITES]
assistant