I can only imagine that starving to death is a terrible fate. So mass starvation must be truly horrific. The gashadokuro is the embodiment of that trauma—a Huge undead giant composed of the countless bones of the starving dead and animated with their desperate hunger.
Like devourers, gashadokuros are terrifying because they can consume characters nearly utterly, and they are even more indiscriminate, gobbling up any living thing in their path. The bones then fall out of the gashadokuro’s rib cage—one explanation for its constant hunger—or are vomited up as a breath weapon.
Personally, I think a gashadokuro’s appearance should reflect the conditions where it was born. A gashadokuro born in a dust bowl might be a sandy thing constantly surrounded by spiraling winds, while a gashadokuro born in a ghetto might have tenement floorboards and cheap shingles stuck among its many bones.
One final note: The gashadokuro’s stat block reads: “Organization solitary.” And 99% of the time that should be the case. But we have a name for that other 1%, one that could make for a hell of a campaign: Attack on Titan.
For years a decanter of endless water was all that kept an isolated valley fertile. When the decanter was stolen, the river dried up and the people starved. Now a gashadokuro tirelessly hunts the bearer of the decanter, and it matters little if the current owner is innocent of the original theft.
Adventurers airlift supplies to a far-flung colony…only to find it deserted. The headman’s diary speaks of failed crops, famine, and growing desperation. Then a gashadokuro erupts from the ground, crippling their flying mounts in gout of bone shards and stranding them far from home.
Even devils avoid the Tantalan Fields. Here sinners used to harvest crops they would never eat and sit at tables where the food turned to ash on their plates. The collective hunger of the souls was enough to create a fiendish gashadokuro that defied the minor devil overseers’ attempts to command or destroy it. They have moved the remaining souls rather than report their failure up the chain of command, leaving the Fields a blind spot that adventurers can take advantage of—if they survive the undead guardian.
—Pathfinder Bestiary 4 121
More on the gashadokuro can be found in Pathfinder Adventure Path #54: The Empty Throne.