The Savage Tide was a plague of destruction and madness which befell the ancient Olman city of Thanaclan, and gave the Isle of Dread its ominous name. It was orchestrated by Demogorgon and his Kopru minions, and unleashed by one of the dreaded Shadow Pearls.
Background
For generations, Thanaclan was a glorious and thriving Olman City-State, but its residents could not have known they had an unseen enemy.
Long before the first Olman settlers landed here from the Saffron Isles, the Isle of Dread had been in the possession of the Kopru; a race of evil aquatic creatures. The Kopru themselves had once commanded a great empire, but by this date, that empire was in sharp decline.
The Kopru had a reputation for three things; their great intelligence, their cruelty, and their absolute devotion to Demogorgon. Working closely with the Demon-Lord, the Kopru plotted for decades with an elaborate plan to destroy the Olman trespassers.
Kopru sorcerers and priests labored long in dark subterranean lairs unfolding their vile plot; the creation of the largest black pearl the world had ever seen.
This was no ordinary pearl; but rather, one of the dreaded Shadow Pearls. Spawned by a gigantic, fiendish oyster, and imbued with Demogorgon's demonic powers, the pearl was both irresistibly beautiful and deadly.
When the great black pearl was completed, The Kopru cleverly left the pearl in a place where they knew the Olman would find it. The trap was set.
Olman pearl fishers soon found the ebony prize and triumphantly brought it back to Thanaclan as a trophy from the Gods. The pearl was then ensconced upon the High Altar of the City Temple. But once in place, the curse of the pearl began, corrupting everything it came in contact with. Soon after, the Olman Gods turned their backs on Thanaclan.
The effects the curse grew ever stronger, and the resulting calamities grew. Terrible storms battered the island, crops failed, wild beasts began rampaging through the city, and a eerie fog descended, covering the entire region. Soon the very ground beneath the city began to shake violently. In a panic, the Olman priests tried desperately to magically cast the pearl into another dimension.
But their efforts only sealed their doom. The pearl opened and an oily, green mist poured forth, engulfing the entire city. Soon after, a great explosion rocked the central plateau of the island, opening up a gateway between worlds.
In a rush of filthy water, the entire city of Thanaclan was consumed by the Abyssal domain of Demogorgon. The entire region was saturated by this dark force, and those Olman not immediately killed were driven completely mad with Savage Fever. This fever infected all of the Olman residents, who soon succumbed into a violent, homicidal rage which consumed the entire population of the island.
