Tidecaller Mentor is a uncommon Creature — Rat Wizard card from Bloomburrow (BLB), collector number 236. Current market price: $0.20 (foil $0.24), TCGplayer market prices via Scryfall.
Menace Threshold — When this creature enters, if there are seven or more cards in your graveyard, return up to one target nonland permanent to its owner's hand.