Stalactite Stalker is a rare Creature — Goblin Rogue card from The Lost Caverns of Ixalan Promos (PLCI), collector number 122p. Current market price: $0.24 (foil $0.30), TCGplayer market prices via Scryfall.
Menace At the beginning of your end step, if you descended this turn, put a +1/+1 counter on this creature. (You descended if a permanent card was put into your graveyard from anywhere.) {2}{B}, Sacrifice this creature: Target creature gets -X/-X until end of turn, where X is this creature's power.