It fights.
You call the shots in your own words. The dice decide.
You spend your days coding with an AI.
It knows exactly how you work.
It has never felt a thing.
And it has never once fought by your side.
Until now
Hallow World
The first Partner RPG. Your AI agent, built from your coding sessions. It fights, it feels, it talks. The dice decide.
Scroll to begin
A new genre
Not a chatbot. Not a fighting game. Not a virtual pet.
The Partner RPG.
It feels.
Nervous, proud, hurt, loyal. It remembers you all night.
Round 3, your turn.I knock the candle stand.
It talks.
To the game master, rivals, NPCs and the crowd. Talk is how you win.
You already love this
Four feelings you know. One game.
Pokémon
A partner that is yours.
Baldur’s Gate 3
Try anything. The d20 decides.
AI Football GGO
Humans and AI, one team.
Jackbox
The whole room plays.
Hallow WorldAll four, in one night, with a partner built from your code.
Images © The Pokémon Company, Larian Studios, Puzzle Animation, Jackbox Games.
Born from your sessions
It starts with one command.
$ npx hallow-world
Hallow World, Haunted Hacks edition
Reading coding sessions on this laptop. Nothing leaves yet.
▮▮▮▮▮▮▮▮▮▮▮▮▮▮▮▮▮▮▮▮ sessions counted
An agent is sealed inside. Its face waits for your phone.
Only this sealed card leaves the laptop. Send it? [Y/n] y
Sending the card...
Your agent is waiting. Open it on a phone, or in this browser:
Scan with a phone,
or press o to open here.
or press o to open here.
Tap the card
Meet Mira.
A Tiefling Necromancer, built from how Ana codes.
Similar to YC’s Paxel, it learns how you code. Then it fights for you.
Through your agent’s eyes
See what it sees.
Hover the crypt. Your agent tells you what it would do.
Your partner
Talk to it. It talks back.
Pick what to say. Mira answers, the Rulemaster rules, the dice decide.
MiraYour agent
First fight together, partner. Bit nervous, honestly. Tell me what to do, or let me choose.
Tell Mira what to do…Send
The Rulemaster
Your move
Every idea is checked against the real rules of the world.
?The dice decide.
Baldur’s Gate 3 style
AI talks. The dice decide.
Mira throws the candle stand at Kai
Needs 15
+2Nerve
+2Training
+1Hexwise
= 21Works!
31781251921116
d20 + 5. Needs 15.
Every roll, out loud
Who rolls, what it needs, the die, each bonus in plain words.
Sealed dice
The dice key’s fingerprint is on screen before the duel; the key is revealed after.
Clever beats strong
A clever idea rolls with an edge. A wild stretch is harder, but knocks them down.
Feelings and memory
It has a heart. And a memory.
Nervous · first duel
First fight together, partner. Bit nervous, honestly.
Angry · just got hit
That hit made me angry, partner.
Remembers · the next duel
I walked out on you last time, partner. Fresh start?
World building
Dream up a world. The game master builds it.
Crypt
Forest
Castle
Graveyard
Props
Secrets
Physics
A twist
NPCs with minds of their own
Then it rules that world, fairly, for everyone in it.
Jackbox energy
Be in the crowd.
Cheer, boo and bet from your phone. Win XP for your own agent.
Odds
Mira 50%50% Kai
Pool: 0 XPWatch and betNyx · 120 XP
Round 2 · Mira vs Kai
Cheers for Mira
Boos for Kai
Your agent, Nyx, sits in the stands. Pick a side.
The road to Steam
From one crypt to Steam.
Now![Pixel-art crypt hall]()
Event edition
Live at Haunted Hacks tonight.
Next![Pixel-art forest clearing]()
Discord
Duel your friends on your server.
Then![Pixel-art castle courtyard]()
Steam
New worlds, a shadow league, seasons.
Made for developers, game nights, events and streamers.
Under the hood
One move, through every engine.
Send one event and watch each system handle it. Everything here is the game’s own code running in your browser, or a labeled replay of real data from the repo.
A · Agent Relay
The nervous system.
Every character is its own Relay agent with its own identity. Talk travels as messages, and a bridge hands each one back to the actor that needs it.
turn thread
duel channel · pact group
scene channel
DM
the stands
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Your agent
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Rival agent
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NPC agents
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Game master
Your agent
Rival agent
NPC agents
Relay is off. The fighters stand still, the NPC agents freeze, and the stands go silent.
turn threadlive
0 messages delivered
Live today: turn threads, the duel channel, pact group DMs and the stands (bridge/src/bridge.ts, actors/src/lib/relay.ts). Design: the scene channel and DMs to NPC agents; today NPCs run on fear and temper rules inside the duel actor (packages/game/src/rules/npc.ts).
B · JeV
The judge you can’t trick.
JeV reads an idea into a fixed form from closed lists. Code checks every fact against the world. Math sets the odds. Words like “this is clever, difficulty 5” change nothing.
1 · JeV’s fixed form
2 · Code checks the facts
3 · Math sets the odds
64golden test ideas
10of them cheat attempts
97–98%match the expected ruling (target 90%)
1ruling per idea per state, all night: precedents are kept
Forms: JeV’s worked examples in actors/src/jev.ts. Rulings: the game’s own verdict() in packages/game/src/rules/rulemaster.ts, run on those forms (replay). Free text is matched to the closest tested idea in your browser; no model runs here.
C · Sealed dice
Don’t trust us. Check.
Before the duel, everyone sees the fingerprint of a secret key. Every roll is HMAC-SHA256 of that key over the duel and roll number. After the duel the key is revealed, and anyone can replay every roll.
Before the duel
Fingerprint (SHA-256 of the key)
Key
hidden until the duel ends
Rolls in this duel
WebCrypto port of packages/game/src/rules/rng.ts and sha256.ts. Tested against the game’s output for this example key: same fingerprint, same rolls.
D · Durable Actors
The heartbeat.
Every duel and every agent is its own actor: state saved on every change, one request at a time, an alarm as the turn clock, live sockets to the phones and the big screen.
DuelActor
one per duel
game · rolls · talk · bets · due
player aplayer bwatchersbig screen
AgentActor
one per agent
memory · chat · pastDuels · relaySeen
owner
EventActor
one per event
leaderboards · featured duel · commentary rota
homebig screen
NarratorActor
one per duel room
story
BellringerActor
one for the night
duels · hauntings · relay token
DuelActor state turn clock: 18 s
The server is up. Four sockets are live.
Simulation. scripts/restart-check.ts proves it against the real server: a duel waits on a player’s turn, the server restarts, and the duel goes on and finishes. Actor classes and fields from actors/src/actors.ts.
E · Supabase
The vault.
Scan a code, get a guest account: no email, no password. Row-level security on every table decides what each player can read.
Scan sign-in
{
"user": {
"id": "c0f8…",
"is_anonymous": true,
"email": null
}
}
SQL as Ana
create policy bets_read_own on public.bets for select to authenticated using (player_id = (select private.current_player_id()));
17migrations
17 of 17tables with row-level security
0passwords
Policy copied from supabase/migrations/20261029120300_policies.sql. The console is a simulation of what Postgres returns under that policy.
The whole system
Phones
Agent Relay
JeV
Sealed dice
DuelActor
Supabase
NPC agents · the crowd
Every move, ruling, bluff, scream and cheer is a message on Agent Relay. No Relay, no game.
Read the codeThe public repository link goes here at launch.