The cicadas start at dawn and do not stop until the streetlights flicker on. That is the first thing you notice about Morioh — the sound. A low, electric scream that rises and falls with the heat, so constant that silence feels wrong, like a held breath.
Morioh sits where the river meets the sea, a town of fifty-eight thousand souls pressed between green hills and grey water. It has a shopping arcade, a high school, a lighthouse, and a serial killer who has been murdering women for fifteen years without anyone noticing. It also has an unusually high number of Stand users — people whose souls have manifested as invisible psychic entities called Stands. Something about this town draws them. Something about this town keeps them here.
What This Game Is
Morioh, 1999 is a sandbox roleplaying game set in the world of Hirohiko Araki's JoJo's Bizarre Adventure: Diamond is Unbreakable. You play a resident of Morioh — a Stand user, or someone who will become one — navigating the sweltering summer of 1999. The town is alive. Threats evolve whether you face them or not. The Arrow is passing from hand to hand, awakening new Stand users every week. A serial killer wears a businessman's smile. Ghosts linger in an invisible alley beside a convenience store. And beneath the riverbed and the old shrine steps, something older than Stands is stirring.
This is not a game about following a pre-written plot. It is a game about a town that breathes. Your choices drive the story. The people you befriend, the enemies you make, the secrets you uncover — these determine what happens. The GM's job is not to steer you toward a prescribed ending. It is to ask: given what you just did, what would Morioh do?
The System
The game runs on the Storyteller System Lite — a d10 dice pool system adapted for fast, dramatic play. When you attempt something dangerous or uncertain, you roll a number of ten-sided dice equal to the relevant Attribute (or two Attributes combined for complex tasks). Each die that comes up 6 or higher is a success. The GM sets a difficulty — the number of successes you need. Your Skills add bonus dice. Two 10s is a critical success. Two 1s is a critical failure.
Stand combat uses a different engine — a matrix of letter-grade stats (A through E) that resolves clashes through direct comparison rather than dice. When your Stand and an enemy Stand collide, you compare Power against Durability, Speed against Speed, Precision against Speed. The higher rank wins. Equal ranks are contested. This makes Stand battles fast, brutal, and tactical.
The full rules for both systems are in the chapters ahead.
What a Session Feels Like
You'll start with an ordinary moment — lunch at Trattoria Trussardi, a shift at Kameyu Department Store, the walk home from Budogaoka High School. The GM will describe the heat, the cicadas, the light. Someone will say something wrong. Someone will notice something out of place. And then the ordinary world will crack open, and a Stand will be standing in the alley where a moment ago there was nothing, and you will have to decide what to do about it.
Between sessions, time passes. You choose a downtime action — training a skill, investigating a lead, strengthening a bond with someone who matters. The GM advances the town's clocks: the Arrow changes hands, Kira claims another victim, rumors spread through the shopping arcade. Morioh does not wait for you. Morioh is always moving.
What You'll Need
You'll need a character sheet — created using the rules in the next chapter — and a willingness to treat Morioh as a real place. Pay attention to the weather. Remember people's names. The town has memory, and so should you.
Your character has nine Attributes, twenty-seven Skills, and — if you're a Stand user — a Stand with six letter-grade parameters and one unique ability that no one else in the world possesses. The Stand is your soul made manifest. It reflects who you are: your deepest needs, your worst fears, the thing you refuse to face. Choose its name from music. Choose its power from your own psychology. The Stand does not lie.
Before You Begin
Read the chapters in order. Making a Character comes first — you'll want your sheet ready. Then Dice & Skill Checks, so you know how to roll. Then Stands & Awakening and Stand Combat, because sooner or later, you will be in a Stand battle. The rest you can absorb as needed.
Welcome to Morioh. The cherry trees have finished blooming. The heat is brutal. The pressure is rising. Somewhere in the dark, an Arrow is flying toward its next target.
It might be you.
