Cauldron Haze

If a creature has multiple instances of persist, the result is largely the same as having just one instance of persist. When the creature is put into a graveyard, each persist ability will trigger. The first one to resolve will return the creature to the battlefield with a -1/-1 counter on it. The rest will do nothing.

If a nontoken creature that gains persist this way is put into a graveyard, that card will be returned to the battlefield with a -1/-1 counter on it. However, because it’s a new object with no relation to its previous existence, that permanent will not have persist.

If a permanent has multiple instances of persist, they’ll each trigger separately, but the redundant instances will have no effect. If one instance returns the card to the battlefield, the next to resolve will do nothing.