Xavier Sal, Infested Captain + Haunted One + Intruder Alarm + Phyrexian Altar

Prerequisites

• There is at least one counter on a permanent you control except Xavier Sal.
• Xavier Sal does not have summoning sickness.
• You control at least one additional nontoken Human, Fungus and/or Pirate that has no more than one +1/+1 counter on it.

Steps

1. 1Activate 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.
2. 2Xavier 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.
3. 3Resolve the Xavier Sal ability, causing you to populate.
4. 4Activate Phyrexian Altar by sacrificing the additional Human, Fungus and/or Pirate, adding one mana of any color.
5. 5When the creature dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
6. 6When the creature enters the battlefield, Intruder Alarm triggers, untapping all creatures.
7. 7Repeat.

Effects

• Infinite colored mana
• Infinite creature ETB
• Infinite creature LTB
• Infinite creature sacrifice triggers
• Infinite death triggers
• Infinite mana creatures you control can produce
• Infinite power for certain creatures until end of turn
• Infinite untap of creatures