Talk:The Witcher 3: Wild Hunt - Guide to Alchemy/@comment-72.50.59.249-20150606030350/@comment-72.128.208.82-20150826070240

At the Barons keep at Crow's Perch you can climb one of the towers. At the top you can then jump over the wall into the topmost part of that tower. Inside are several loot containers. One has the diagram for Hybrid Oil.