How to Make Fever Tonic in Kingdom Come Deliverance 2

In "For Whom the Bell Tolls," a main quest in Kingdom Come: Deliverance 2, Hans requires your assistance at Trosky Castle, beginning with crafting a Fever Tonic. Here's how to obtain the recipe and brew the potion.

Locating the Fever Tonic Recipe:

Access to the Surgeon's Workshop, containing the recipe, can be gained in two ways: Discreetly infiltrate the workshop, or persuade the chamberlain. To persuade him, complete the "For Whom the Bell Tolls" objectives up to delivering the horseshoe. Then, speak with Cook Fanka at the forge; offering to help with her locked chest grants access to the noble's kitchen. Convince the ailing chamberlain you can assist him (skill checks involved) to gain workshop access. Crafting a digestive potion alongside the Fever Tonic further enhances your chances. If skill checks fail, steal food, proceed to the courtyard's other side, and bribe the guard with the stolen food to access the kitchen and subsequently, the workshop.

The Surgeon's journal, detailing the recipe, is located on the bookshelf within the workshop.

Brewing the Fever Tonic:

The necessary herbs are already present on the surgeon's station. Follow these steps:

1. Pour wine into the cauldron.
2. Add 3 handfuls of Feverfew.
3. Lower the heat and boil for 2 turns of the sandglass.
4. Grind a handful of Elderberry Leaves.
5. Add the ground Elderberry Leaves.
6. Add 2 handfuls of Ginger.
7. Obtain a phial from the bottom-left shelf.
8. Distill the tonic using the Still.

Additional herbs are available in the chest if needed.

Completing the Quest:

After brewing the Fever Tonic, locate Thomas. If you have the chamberlain's trust (due to the digestive potion), return with both potions. Otherwise, use the noble's kitchen to reach the chapel and find Thomas and Adele. Speak with Adele to conclude the quest.