This hidden cult holds that the Mark of Storm is a gift from the Devourer, not Arawai and Kol Korran. The Kraekovar believes that great bearers of the Mark of Storm live on after death as krakens in the deeps and will arise when called to ensure Lyrandar dominance over sea, sky, and even land.
Source: Eberron Campaign Guide
The basic doctrine of House Lyrandar maintains that the Mark of Storms is a blessing granted by Arawai and Kol Korran, a gift to help the Khoravar prosper. However, these is a sect within the house that claims that holds more sinister beliefs. These cultists say that their mark is a gift of the Devourer, and that it is intended to be used as a weapon—that the Khoravar are meant to assert their dominion over Khorvaire with hurricanes and lightning. This sect maintains that their greatest visionaries have become krakens who dwell in the deepest waters and guide their followers through visions; as such they call themselves the Kraekovar or “Kraken’s Brood.” Kraekovar heirs learn to use their dragonmarks in unusual and destructive ways, specializing in lightning. Other Lyrandar heirs say that this represents a fundamental corruption of the dragonmark—that the mark isn’t meant to be used as a weapon—and that this in turn causes the Kraekovar to become unstable and sociopathic. While the Kraekovar claim that their power ultimately flows from the Devourer, they don’t share any common cause with the Three Faces of the Wild or with zealots; they are loyal to their own elders—whom they believe to be immortal krakens—and to their vision of a nation ruled by Khoravar storm kings.
Source: Dark Six - The Devourer