Finding the Royal Treasury Key in Kingdom Come: Deliverance 2's Oratores quest can be tricky. This guide provides a clear walkthrough.
The Oratores quest, a lengthy main quest, requires retrieving the Royal Treasury Key after assisting Vavak. The key is hidden in an unexpected location.
Locate the outhouse in Vavak's backyard (see map below).
Examine the toilet inside the outhouse. An "Investigate" prompt will appear. Clicking it will reveal the key. Note: this will dirty Henry; wash up afterward to avoid dialogue issues with NPCs.
With the key, return to Zizka and Rosa, then proceed with Samuel to explore the underground passages. The quest continues from there.
This concludes the guide on obtaining the Royal Treasury Key. Check out The Escapist for more Kingdom Come: Deliverance 2 tips and guides, including Lower Semine woodcutters' treasure locations and optimal perk choices.