Kulrath Knight is a uncommon Creature — Elemental Knight card from Shadowmoor (SHM), collector number 190. Current market price: $0.77 (foil $21.70), TCGplayer market prices via Scryfall.
Flying Wither (This deals damage to creatures in the form of -1/-1 counters.) Creatures your opponents control with counters on them can't attack or block.