Ethereal Usher is a uncommon Creature — Spirit card from Ravnica: City of Guilds (RAV), collector number 47. Current market price: $0.26 (foil $1.50), TCGplayer market prices via Scryfall.
{U}, {T}: Target creature can't be blocked this turn. Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)