Obelisk Spider is a uncommon Creature — Spider card from Hour of Devastation (HOU), collector number 141. Current market price: $2.52 (foil $17.18), TCGplayer market prices via Scryfall.
Reach Whenever this creature deals combat damage to a creature, put a -1/-1 counter on that creature. Whenever you put one or more -1/-1 counters on a creature, each opponent loses 1 life and you gain 1 life.