Cauldron of Souls is a rare Artifact card from Commander 2016 (C16), collector number 246. Current market price: $6.86, TCGplayer market prices via Scryfall.
{T}: Choose any number of target creatures. Each of those creatures gains persist until end of turn. (When it dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)