Krydle of Baldur's Gate is a uncommon Legendary Creature — Human Elf Rogue card from The List (PLST), collector number AFR-343. Current market price: $0.31, TCGplayer market prices via Scryfall.
Whenever Krydle deals combat damage to a player, that player loses 1 life and mills a card, then you gain 1 life and scry 1. Whenever you attack, you may pay {2}. If you do, target creature can't be blocked this turn.