Paul Deacon, codename Hex, is a long-serving Delta Green operative, ex-Marine, and CIA cyber security specialist who entered the H-Cell Chronicle already significantly damaged. A Deep One called Marsh — who possessed intimate prior knowledge of his life — kidnapped his best friend, an experience that left Hex with amnesia, compulsive dissociative looping behaviour, and episodes in which the Azathoth void overlays his normal perception. He is described at the campaign's opening as mentally broken: unable to settle, compulsively humming a tune from his previous encounter, and waking from dreams of constant loops.
Hex serves as the cell's intelligence and cyber operations specialist, identifying the Deep Energy financial irregularities through technical means and handling the initial decoded cipher message. He is also — unusually for someone in his psychological state — the operative who consistently asks the strategically correct questions: whether the filament heart might be the anchor from the cipher message, whether Shoggoths and other entities coexist or compete, whether the information they have received is all coming from the same source.
His Azathoth episodes escalate through the campaign: from perceiving movement on the filament heart's surface, to the humming affecting Hanover, to a full dissociative episode at the Oasis of Whispers pool where he lowers his weapon, walks to the water's edge, and kneels as though awaiting his master. He and Hanover are both recorded as killed in the final session at the Oasis — ending the campaign's WWII thread with the heaviest possible casualties.