Core of Elements
On the map
Eastern Plaguelands- drops almost everywhere
Progress
Truth be told, I use the cores to create Frostfire armor. It is the armor used by the mages battling in Naxxramas. Without you and others like you, we would most definitely be losing this war.
With that said, bring me more cores and I shall grant you more insignias.
Completion
You perform a great service for us, <name>. Well done!