The Whispering Hillock

The Whispering Hillock is a main quest in Velen, and it contains what is probably the most debated choice in The Witcher 3. Geralt can stumble on it by himself while exploring, in which case it shows up as a secondary quest, but most players reach it through Ladies of the Wood, when the Crones of Crookback Bog send him to deal with a “problem” that has been killing the people of Downwarren.

The voice under the oak

The trail leads to an ancient oak on a hill near the bog. A voice tells Geralt to stay away, a werewolf prowls near the entrance, and a flooded cave winds its way down to the tree’s roots. There, a beating heart holds a trapped spirit. It speaks with a woman’s voice, claims it was imprisoned by the Crones, and offers a deal: set it free and it will save the orphans the Ladies of the Wood are keeping at Crookback Bog.

Free it or kill it

To release the spirit, Geralt has to gather three things: a raven feather, the spirit’s own bones, which he remarks do not look human, and a wild black horse that he must calm with Axii and ride into the cave. The ritual moves the spirit into the horse, and it gallops off as the creature later known as Black Beauty. Geralt can also start the ritual and simply refuse to finish it, letting the spirit fade quietly. If he refuses to help at all, the spirit summons endregas to defend itself, and Geralt has to cut through the roots and destroy the heart.

Why the choice matters

Nothing about this decision is clean. The spirit may be telling the truth about the children, and it may also be the thing that has been killing villagers. The game does not reveal which is worse until Return to Crookback Bog, and even then there is no happy ending on either road, only different people paying the price. That is exactly why players still argue about it.

Walkthrough

Go to the Ancient Oak near Downwarren and follow the voice with your witcher senses. Wolves may attack on the eastern side.
On the western side, find the cave entrance guarded by a werewolf, next to an Igni Place of Power.
Follow the flooded tunnel to the heart in the roots and talk to the spirit.
To free it: take a raven feather from the harpy nest west of Downwarren, find the spirit’s bones in the swamp with your witcher senses (watch out for a water hag and drowners), and calm a wild black horse with Axii.
Ride the horse back into the cave through the new opening and choose to release the spirit, trick it into dying, or kill it.
To destroy it instead: fight off waves of endrega workers and attack the roots until you can strike the heart.

Quest Consequences & Choices

The outcome plays out in Return to Crookback Bog. Kill the spirit, and Downwarren survives (although the witch hunter Graden hangs some villagers for witchcraft), but the Crones take the orphans. Anna lives but loses her mind, and the Baron takes her away to find a cure. Free the spirit, and it saves the children, who later end up in the care of Marabella in Novigrad, but it slaughters most of Downwarren. The Crones punish Anna by turning her into a water hag, she dies when the curse is lifted, and the Baron hangs himself.