Goblin Chieftain is a mythic Creature — Goblin card from Special Guests (SPG), collector number 135. Current market price: $5.99 (foil $7.70), TCGplayer market prices via Scryfall.
Haste (This creature can attack and {T} as soon as it comes under your control.) Other Goblin creatures you control get +1/+1 and have haste.