Fizzleberry Wine is an elvin beverage that are served occasionally to adults in the series. The substance is not alcoholic, but has similar effects.
Fizzleberry wine was first mentioned after midterms, when Alvar was visiting Everglen. He drank an entire cup in one gulp. It is later revealed in the series that the wine is rumored to have aided in causing Caprise Redek's brain injury.
When Keefe is part of the Neverseen's order, he learned part of the code for Fintan's cache after Fintan drank too much fizzleberry wine.
In Unlocked, when Sophie and Oralie access Oralie's cache, Oralie says that Kenric claimed she had too much fizzleberry wine. Oralie believes he might've been lying.