How to Make Fever Tonic in Kingdom Come Deliverance 2

In Kingdom Come: Deliverance 2, Hans's main quest, "For Whom the Bell Tolls," requires crafting a Fever Tonic to save someone at Trosky Castle. Here's how:

Locating the Fever Tonic Recipe:

The recipe resides within the Surgeon's Workshop in Trosky Castle. Access is gained in two ways: either by stealthily entering the workshop or by convincing the chamberlain you can create a digestive potion for him. After delivering the horseshoe in "For Whom the Bell Tolls," speak with Cook Fanka. Offering to help with her locked chest grants access to the noble's kitchen, where the ailing chamberlain can be found. Successful skill checks allow access to the workshop. If skill checks fail, steal food, proceed to the courtyard's other side, bribe the guard with the stolen food, and sneak into the workshop. Inside, find the Physician's journal on the bookshelf.

Brewing the Fever Tonic:

The necessary herbs are already at the surgeon's station. Consult the Fever Tonicum recipe in the journal and 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 should you need them.

Completing the Quest:

After brewing the Fever Tonic, deliver it to Thomas. If you gained the chamberlain's trust by providing a digestive potion, return with both potions. Otherwise, use the noble's kitchen to reach Thomas and his sister, Adele, in the chapel. Speak with Adele to conclude the quest.