Steamflogger Boss is a rare Creature — Goblin Rigger card from Future Sight (FUT), collector number 121. Current market price: $0.54 (foil $9.72), TCGplayer market prices via Scryfall.
Other Riggers you control get +1/+0 and have haste. If a Rigger you control would assemble a Contraption, it assembles two Contraptions instead.