Brine Seer is a uncommon Creature — Human Wizard card from Urza's Destiny (UDS), collector number 28. Current market price: $0.31 (foil $2.28), TCGplayer market prices via Scryfall.
{2}{U}, {T}: Reveal any number of blue cards in your hand. Counter target spell unless its controller pays {1} for each card revealed this way.