Archpriest of Iona is a rare Creature — Human Cleric card from Zendikar Rising Promos (PZNR), collector number 5p. Current market price: $0.35 (foil $0.50), TCGplayer market prices via Scryfall.
Archpriest of Iona's power is equal to the number of creatures in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.) At the beginning of combat on your turn, if you have a full party, target creature gets +1/+1 and gains flying until end of turn.