Infinite charge counters on a permanentInfinite creature ETBInfinite creature LTBInfinite creature sacrifice triggersInfinite death triggersInfinite mana creatures you control can produceInfinite power for certain creatures until end of turnInfinite untap of creatures
How it works
Activate Xavier Sal's first ability by tapping it and removing a +1/+1 counter from the additional nontoken Human, Fungus and/or Pirate if it has one, or any counter from another permanent you control otherwise.
Xavier Sal triggers, causing it and all other creatures you control that share a creature type with it to get +2/+0 and gain undying until end of turn.
Resolve the Xavier Sal ability, causing you to populate.
Activate Spawning Pit by sacrificing the additional Human, Fungus and/or Pirate.
When the creature dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
When the creature enters the battlefield, Intruder Alarm triggers, untapping all creatures.
Resolve the Spawning Pit ability
Repeat.
This intricate loop hinges on leveraging **Intruder Alarm** to turn every creature death and entry into a cascading untap fest. By sacrificing a creature to **Spawning Pit**, you trigger **Haunted One** (granting your commander undying) so it immediately returns with a +1/+1 counter. That new entry wakes up the entire board via **Intruder Alarm**, including **Xavier Sal, Infested Captain**, who can then strip that very counter away to populate your token army while keeping the loop going.