Starfield Mystic is a rare Creature — Human Cleric card from Duskmourn: House of Horror Commander (DSC), collector number 105. Current market price: $0.35, 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.