Rohirrim Chargers is a rare Creature — Human Knight card from Tales of Middle-earth Commander (LTC), collector number 496. Current market price: $0.42 (foil $0.37), TCGplayer market prices via Scryfall.
You may exert this creature as it attacks. (It won't untap during your next untap step.) Whenever you exert a creature, reveal cards from the top of your library until you reveal an Equipment card. Put that card onto the battlefield attached to that creature, then put the rest on the bottom of your library in a random order.