How to Make Fever Tonic in Kingdom Come Deliverance 2

In "For Whom the Bell Tolls," a Kingdom Come: Deliverance 2 main quest, Hans needs your help at Trosky Castle. This involves brewing a Fever Tonic.

Locating the Fever Tonic Recipe:

Access to the Surgeon's Workshop, containing the recipe, can be gained in two ways: stealthily entering the workshop, or convincing the chamberlain by offering to create a digestive potion. If you choose the latter and fail the skill checks, steal some food, proceed to the courtyard's other side, and use the kitchen there (after bribing the guard with the stolen food). This allows you to sneak to the workshop.

Alternatively, completing "For Whom the Bell Tolls" objectives up to delivering the horseshoe, then speaking with Cook Fanka, will lead you to the noble's kitchen and the ailing chamberlain. Successfully convincing him to grant access to the workshop will also work. The journal detailing the recipe is located on the bookshelf inside.

Brewing the Fever Tonic:

The necessary herbs are readily available 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 (and optionally, a digestive potion), deliver the potion(s) to the chamberlain (if you have his trust) or proceed to the chapel to find Thomas and Adele. Speaking with Adele concludes the quest.