Xavier Sal, Infested Captain + Haunted One + Thornbite Staff + Carrion Feeder

Xavier Sal, Infested Captain

Haunted One

Thornbite Staff

Carrion Feeder

How it works

1. 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.
2. 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.
3. Resolve the Xavier Sal ability, causing you to populate.
4. Activate Carrion Feeder by sacrificing the additional Human, Fungus and/or Pirate.
5. When the creature dies, its undying ability and Xavier Sal trigger.
6. Resolve the creature's undying trigger, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
7. Resolve the Xavier Sal trigger, untapping it.
8. Resolve the Carrion Feeder ability, putting a +1/+1 counter on it.
9. Repeat.