The goddess Laithe of storms and the wild sea was once worshiped the few sea going humans of the Glass Gulf and some of the gnomish raiders and pirates that ventured there. Not long after the formation of the Kingdom of Vardor, with the diminishment of gnomish pirates and a human god for the coastal tribes to turn to, she was forgotten by those who lived above the water. Her island temple eventually cracked and her power began to diminish.
While the storms of the sea to the west of Vardor still promised worship of those seeking to pass through treacherous waters, a more gentle wind goddess, Anaith, was passed among the humans of Vardor by those of the western coast who worshiped her. When she guided Vardor ships to her home, Stormguard, Laithe lost all chance at regaining a place among sailors. Her power waned, but did not fail completely, for the merfolk of the Glass Gulf still worshiped her in their pantheon.
So she bided her time, waiting for an age when the merfolk would become more active near the surface, or when pirates would flourish again and call on her vengeful name. She is on the verge of madness, but yet has power with which to tempt mankind to her sanctum.
Her temple, broken and standing upon pillars of stone on the coast of a small cliff island, still holds the weapon with which she armed her high priest: the Stormspark. This weapon shapes itself to suit the wielder and can imbue itself with lightning damage (once per day gain 2d6 lightning damage for the next 6 attacks, maximum duration 1 hour). In the hands of the high priest of Laithe, the Stormspark can seed the clouds with potential, causing lightning to strike (as Call Lightning spell, but with strike points determined randomly each turn without an action).