the front side of Halo Fountain
the back of a classic MtG card
the front side of Intruder Alarm
the back of a classic MtG card
the front side of March of the Machines
the back of a classic MtG card

Color Identity: W, U

Initial Card State

  1.  All permanents on the battlefield.

Notable Prerequisites

  1. Halo Fountain does not have summoning sickness.
  2. You control a creature that can tap to produce at least one white mana.

Steps

  1. Activate a creature you control by tapping it, adding one white mana.
  2. Activate Halo Fountain's first ability by paying one white mana, tapping and untapping it, creating a 1/1 Citizen creature token.
  3. When the Citizen enters the battlefield, Intruder Alarm triggers, untapping all creatures.
  4. Repeat.

Results

  1. Infinite creature tokens.
  2. Infinite creature ETB.
  3. Infinite mana creatures you control can produce.
  4. Infinite untap of creatures.
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