Starfield Mystic is a rare Creature — Human Cleric card from Core Set 2020 Promos (PM20), collector number 39p. Current market price: $1.42 (foil $2.88), TCGplayer market prices via Scryfall.
Enchantment spells you cast cost {1} less to cast. Whenever an enchantment you control is put into a graveyard from the battlefield, put a +1/+1 counter on this creature.