Herald of Torment is a rare Enchantment Creature — Demon card from Born of the Gods (BNG), collector number 75. Current market price: $0.30 (foil $0.46), TCGplayer market prices via Scryfall.
Bestow {3}{B}{B} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached.) Flying At the beginning of your upkeep, you lose 1 life. Enchanted creature gets +3/+3 and has flying.