The ingredient Thorn Hook comes from the plant "Thorn Hook," found in Dementia caves. There are actually 2 varieties of this plant, both of which yield the same ingredient.
22 guaranteed samples can be found. The places with the highest numbers of samples are:
- 5 samples are in the Howling Halls, Congregation Chambers zone
- 3 samples are in Dulphumph gro-Urgash's House in Deepwallow
- 3 samples are in Erver Devani's House in Deepwallow
It can also be found randomly in Ahjazda's inventory and in some loot chests.