Questions, answered.

A desktop game where an AI Dungeon Master runs narrative tabletop campaigns — solo or with remote friends — while a deterministic rules engine handles everything mechanical: dice, combat, saves, conditions, spell slots, hit points. The AI tells the story; the engine enforces the rules. Neither does the other's job.

The app is free. AI features (the DM, AI campaign and character generation) run on your own Claude API key, billed by Anthropic at raw usage cost with zero markup from us. A live meter shows the session's spend, and model/verbosity dials let you tune cost to taste. Manual character building and joining a friend's session cost nothing and need no key.

It's a personal credential from Anthropic (the makers of Claude) that lets the app request narration on your behalf. Setup takes about two minutes: create a free account at console.anthropic.com, add a balance, copy the key into the app's settings. The balance draws down automatically as you play — you never pay more than exactly what's used.

Your key is stored locally and requests go directly from your machine to Anthropic — we never see your key or your sessions.

No. One player per session funds the AI DM; everyone else plays free. Parties commonly take turns hosting across sessions so the cost rotates.

Never. Language models are unreliable accountants — left in charge, they invent rolls and forget hit points. In The Reality Machine every die is rolled by the deterministic engine (or by you, in your own dice box), every modifier comes from your actual sheet, and the math prints in the combat log where you can check it. The AI narrates the results; it cannot change them.

All twelve classes with their subclasses and signature systems working mechanically — Rage, Ki, Metamagic, Wild Shape with real beast stat blocks, Portent, Battle Master maneuvers, Eldritch Invocations, Divine Smite, Sneak Attack, Weapon Mastery, and so on. Spellcasting follows the 2024 rules: slots, upcasting, concentration, prepared casting, cantrip scaling. Conditions, advantage/disadvantage, damage typing, reactions, and death saves all resolve in the engine. The features page lists everything.

No. The Reality Machine is an independent game built on the System Reference Document 5.2.1, which Wizards of the Coast publishes under the Creative Commons CC-BY-4.0 license. It is not affiliated with, endorsed, or approved by Wizards of the Coast. If you know the world's most popular tabletop RPG, you'll feel at home; nothing here requires their trademarked content.

Peer-to-peer. The host creates a campaign, sends an encrypted invite, and your machines talk to each other directly — there is no game server holding your campaign. Each player controls their own character from their own machine, with in-character and out-of-character chat kept as separate feeds. If someone drops, they rejoin and the story is waiting.

Your campaigns and characters live in an encrypted database on your own computer. Invites and notifications are pair-encrypted to their recipient; campaign channels are encrypted under a secret distributed only inside those encrypted invites; friending is pinned to write-once public keys. Narration requests go from your machine directly to Anthropic under your key. We don't run accounts, we don't collect your sessions, and there's no corporate server between you and your friends.

Absolutely — solo play is a first-class mode. The AI DM runs the world and every NPC; the engine runs the fights; your campaign persists across sessions and story arcs just like a group game.

Windows 10/11 (64-bit) today. The app is built on cross-platform foundations, and macOS/Linux builds are planned after the beta stabilizes.

No. The engine knows them for you — it computes your modifiers, offers only legal actions on your turn, and shows the math as it happens. Veterans get fidelity; newcomers get guardrails. Ask the DM anything in plain language and the table keeps moving.

Any Claude model your API key can access. Pick a top model for the richest narration or an efficient one for cheaper sessions, and switch per campaign. Verbosity settings (terse → cinematic) further tune both feel and cost.

It depends on model and verbosity, which is why the app shows a live meter instead of us quoting a number. Terse settings on an efficient model typically run well under a dollar an hour of play; rich narration on the top model costs a few dollars for a long session. One player covers it, or the party rotates.