Gryphon Rider's Stormhammer

Gryphon Rider's Stormhammer is a one-hand mace. It gives a bonus to strength.

Source
This item is a quest reward from the.

Background
The mystic Stormhammers are forged deep within the secret chambers of the aviaries.

Most sacred to the dwarves is the enchanted forge that lies at the heart of each aviary. It is here that the magical weapons known as Stormhammers are fashioned. A Stormhammer, when thrown, strikes with the fury of lightning and the force of thunder. This destructive weapon, combined with the indomitable spirit of the gryphon riders, justifies their position as masters of the skies.

The Wildhammer dwarves' signature weapon, this dwarven battle hammer is beautifully crafted, with a lightning bolt patter carved into the polished wooden haft and clouds and lightning etched into the faceted metal head. Even the leather wrapped around the handle is mottled to suggest clouds and rain. The wielder swinging the hammer can cause a copy of the weapon to appear and fly towards the target, allowing it to be used as a ranged weapon.

The signature weapon of elite gryphon teams, storm hammers must be rededicated to their owners each year. The ceremony is held every solstice in the great halls of the gryphon aviaries. The details of the ceremony are secret, but they are said to involve chanting, solemn oaths, and terrible hangovers the next day.