Arcane Cache Key

The Arcane Cache Key drops from the following Azsh'ari naga in Nazjatar:
 * Azsh'ari Invoker
 * Azsh'ari Neophyte
 * Azsh'ari Oracle
 * Azsh'ari Stormsurger
 * Azsh'ari Stormwitch

As a quest objective
This item is an objective of Arcane Cache (quest).