Toxic 
Potion II
No known way to obtain it. The workstation that makes it cannot be built.
There is a recipe for the Toxic Potion II (Book writing) in the game files, but no workbench offers it and nothing unlocks it, so it cannot be made.
It is an old recipe from before alchemy worked by runes, made from Alcohol with the first Toxic Potion (Book writing) and Brimstone, neither of which can be had.
How to obtain
Sources, all out of reach (1)
Craft
| Workbench | Ingredients | Duration | Tech points |
|---|---|---|---|
| — |  Alcohol ×1  Toxic Potion ×1  Brimstone ×1 | 6 | 12 |