Nalia de'Arnise is a mythic Legendary Creature — Human Rogue card from Alchemy Horizons: Baldur's Gate (HBG), collector number 244.
You may look at the top card of your library any time. You may cast Cleric, Rogue, Warrior, and Wizard spells from the top of your library. At the beginning of combat on your turn, if you have a full party, put a +1/+1 counter on each creature you control and those creatures gain deathtouch until end of turn.