Connor discovered this formula, derived specifically from Anther/ Stamen of the Anthralily.
Fermenting the anther, rather than the whole plant or petals (see Anthracyllin), provides very stimulating and psychoactive effects.
It is at first only a stimulant and dopamine/ serotonin reuptake inhibitor, but as use is continued, it causes live flashback hallucinations. (For example, someone who is high on Anthracaine can function normally from an outside perspective, but the user is likely seeing things happen through altered memories.)
For example. Lets say the user is Lee. Lee has many traumatic memories revolving around A- his murder of Amanda, and B- Rei and Connor "abandoning" him.
While he is using anthracaine, years after these events, he may see other people as people from his memories. He may hallucinate Vi as Amanda, despite whatever Vi is doing. If Vi were picking flowers, he would see Amanda picking flowers. If Vi were verbally abusing him, he would hear and see Amanda's image verbally abusing him.
The user is still connected to reality and functional, but are trapped in their prevalent memories. Whatever memories that person would be thinking about often. This is very detrimental with persons who have PTSD.
That's only the hallucinogenic part.
The strength that nymph types gain from this drug are not completely unlike steroids- however- it has more effects on magic than physical strength.
When used in tandem with the injection of synthetic nymphs, a type of magic, the nymph specifically may become very, very powerful compared to its host, and makes the risk of complete possession very high.
When Anthracaine comes into contact with humans or sylphs in an undiluted form, it absorbs their magic. This makes it seem like it is causing them to be sick from it, but the sudden loss of magic, which is life force in farther earth, is what causes the debilitating disease.
In this sense, Anthracaine can be used to take and store lifeforce, however, this would never be implemented as why the substance harmed humans and sylphs wasn't ever completely understood.