Frostreaper

Frostreaper is one of the Blades of the Fallen Prince.

Source
This item is a quest reward from The Call of Icecrown.

Trivia

 * The flavor text is a quote from the Wrath of the Lich King trailer.
 * Frostreaper used to be the name of the offhand blade in alpha before it switched with it's sister blade, Icebringer.