Krenko, Tin Street Kingpin is a rare Legendary Creature — Goblin card from Foundations Jumpstart (J25), collector number 572. Current market price: $2.90, 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.