Judith, the Scourge Diva is a rare Legendary Creature — Human Shaman card from Ravnica Allegiance Promos (PRNA), collector number 185p. Current market price: $0.36 (foil $1.21), TCGplayer market prices via Scryfall.
Other creatures you control get +1/+0. Whenever a nontoken creature you control dies, Judith deals 1 damage to any target.