Krenko, Tin Street Kingpin is a rare Legendary Creature — Goblin card from Secret Lair Drop (SLD), collector number 1027. Current market price: $42.51 (foil $46.89), TCGplayer market prices via Scryfall.
Whenever Krenko attacks, put a +1/+1 counter on it, then create a number of 1/1 red Goblin creature tokens equal to Krenko's power.