The Hearts of Stone Add-on for The Witcher 3: Wild Hunt has 13 achievements.
Be under the influence of seven potions or decoctions at the same time.
Slide downhill uninterrupted for at least 10 seconds.
Kill 20 cows.
Collect all available Ofieri armor and horse gear, and at least one Ofieri sword.
Kill 3 opponents with their own arrows.
Finish the "Hearts of Stone" expansion.
Recreate all of Iris' nightmares in the Painted World.
Defeat all the fallen knights and loot their campsites.
Participate in all the activities at the wedding.
Buy all the items put on the block at the Borsodis' Auction House.
Kill the prince cursed into a toad.
Provoke all Iris von Everec's Nightmares into fighting you at the same time and defeat them.
Win a round of gwent with a total strength of at least 187.