Oddly enough, the tale of Isfet-Ptah is one more commonly recalled by the Kami
than most mortal species - since the first mortal records do not hint at the existence of Isfet-Ptah until over 1000 years after The Spirit Kings Vanished
and all the rest of the Six Husks had been identified, all tales and myths from before this time have come from the strange beings known as Kami
In these most ancient of stories, the Kami
speak of a being known only as "The Cumulonus"('Stormeater' in their ancient tongue) that traveled the skies, killing Kaminari Kami
and other sky-based Kami
with reckless abandon as it spent its time devouring all sorts of creatures that dwelled in the skies above, hiding itself among the skies and feeding on mortals far below as they lay on their backs, gazing longingly up at the skies as their eyes, gazing unknowingly far up at the Isfet-Ptah in the skies above disguised as the clouds, slowly were robbed of aspects of their personality and mind by its awful power.
In these tales, the Kami
speak of it as a bringer of calamity and unprecedented natural disasters, and as it devoured the Kami
known as Kaminari in charge of bringing thunderstorms and storms across Zheng-Kitar it would transform them into more vicious superstorms that bordered on and frequently became natural disasters - so good was it at its job, the Kami
say, that their constant warnings of mortals long past accidentally entered the beast's name into the lexicon of the beings of Zheng-Kitar as the name for storm clouds: Cumulonimbus Clouds. Otherwise, its time before mortal recording was one of terror, unleashing superstorms and calamities, and stealing away aspects of mortal minds as it dwelled amongst the skies of the world unseen.
It is said that its discover at the hands of Mortals was by complete chance at the hands of an ancient Tarthan
High Lord known as Darragh(Full name Darragh O'Leary O'Houlihan
) who pioneered a master-class arcane ritual designed to divinate the weather patterns of the country for the next hundred years - and accidentally ended up divining the existence of Isfet-Ptah among the skies, though doing so provoked its' wrath that nearly leveled the fledgling Tarthan
Empire. In the ensuing centuries of conflict that resulted, entire swathes of ancient Tarthus had their minds altered and dimmed by Isfet-Ptah's unholy power - though its ultimate fate is not documented, it is known to have been sealed away at some point.