Feldon, Ronom Excavator is a rare Legendary Creature — Human Artificer card from The Brothers' War Promos (PBRO), collector number 135p. Current market price: $0.70 (foil $0.66), TCGplayer market prices via Scryfall.
Haste Feldon can't block. Whenever Feldon is dealt damage, exile that many cards from the top of your library. Choose one of them. Until the end of your next turn, you may play that card.