Hearthstone event will award you a card pack for every daily quest

Hearthstone’s latest event, in celebration of the Year of the Raven, will reward you with a free card pack everytime you complete a daily quest.

Find out what else to expect from Hearthstone's Year of the Raven.

These free card packs could be from any of Hearthstone’s expansions, including the upcoming Witchwood expansion. However, you won’t get to access your Witchwood card packs until after the expansion goes live in April.

from
https://www.pcgamesn.com/hearthstone/hearthstone-year-of-the-raven-event