Slimefoot and Squee | Pitiless Plunderer | Altar of Dementia (and one other card)

Creature with Persist or Undying

Cards

The persist or undying creature doesn't have a -1/-1 or +1/+1 counter on it, respective to its ability.
You control a Saproling.

Activate
Altar of Dementia twice by sacrificing the persist or undying creature and
Slimefoot and Squee.
When
Slimefoot and Squee and the other creature die,
Pitiless Plunderer triggers twice and the other creature's persist or undying ability triggers.
Resolve the
Pitiless Plunderer triggers, creating two Treasure artifact tokens.
Resolve the persist or undying trigger, returning the creature from your graveyard to the battlefield with either a -1/-1 or +1/+1 counter on it.
Activate
Altar of Dementia by sacrificing the undying or persist creature.
When the creature dies,
Pitiless Plunderer triggers, creating a Treasure token.
Resolve the
Altar of Dementia ability.
Activate the Treasures by tapping and sacrificing them, adding ({B} magic symbol) ({R} magic symbol) ({G} magic symbol) .
Activate
Slimefoot and Squee by paying ({1} magic symbol) ({B} magic symbol) ({R} magic symbol) ({G} magic symbol) and sacrificing a Saproling.
When the Saproling dies,
Pitiless Plunderer triggers, creating a Treasure artifact token.
Resolve the
Slimefoot and Squee ability, returning it and the persist or undying creature from your graveyard to the battlefield.
When
Slimefoot and Squee enters, it triggers, creating a 1/1 Saproling creature token.
Activate a Treasure by tapping and sacrificing it, adding ({1} magic symbol) .
Repeat.