Play D&D solo with an AI game master A table for one, a campaign that lasts.

What an AI game master does well, and where it needs you

An AI game master never cancels, never tires of your favorite tavern, and will improvise a smuggler’s daughter with a grudge at a moment’s notice. It describes, voices every NPC, and says yes to strange plans. For solo play, where the alternative is a stack of oracle tables and your own imagination, that is a remarkable partner.

It has blind spots, too, and knowing them is most of the craft:

• It isn’t a rules engine. It knows the shape of common rules but will misremember a spell or a modifier. You have the final word on the rules.
• It doesn’t roll real dice on its own. Ask a language model to “roll a d20” and it writes a plausible number, often a dramatic one. More on honest dice below.
• It leans agreeable. Left alone, it tends to let plans succeed. Tell it you want real consequences.
• It needs a memory system. A campaign outgrows any context window within a few sessions.

This guide uses Dungeons & Dragons as its example because it’s the game most people know, but everything here works for any tabletop RPG, from rules-light indie games to crunchy tactical systems. On LoreWeaver, a campaign is one player and one storyteller. If you’re new to roleplaying with an AI at all, how to roleplay with AI covers the basics first.

Start with a session zero

Groups run a session zero to agree on the game before anyone rolls. Solo, you’re agreeing with yourself and the storyteller, and writing it down is what makes the agreement stick. Settle these:

1. Tone and genre. Heroic high fantasy, grim survival, gothic horror, or swashbuckling intrigue.
2. System and crunch. Which edition or game, and how strictly to follow it. “Rules-light, fiction first” is a fine answer.
3. Starting level and situation. Where your character is, and what problem is already in motion.
4. Lines and veils. Content you never want (lines) and content that can happen off screen (veils).
5. How dice work. You roll, the world rolls, or a mix. Decide before the first fight.
6. The GM’s habits. How long replies should be, when to call for rolls, and how hard to push back.

Then put it where the storyteller reads it. In LoreWeaver, the world’s premise holds the setting, the tone field holds the mood, and the style rules hold your table rules. Style rules that work well for solo play:

• Ask me to roll whenever an outcome is uncertain, name the check and the DC first, and wait for my result.
• Narrate consequences, never my character’s choices or feelings.
• Let my plans fail when the dice or the fiction say so.
• Keep combat to one exchange per reply, and end every reply at a decision.

You don’t have to start from scratch: plenty of community worlds in the Hub’s fantasy collection come with lore and openings, and a world you start from the Hub becomes your own copy, ready to adjust. For tone ideas, browse high fantasy and dark fantasy. For house rules that change during the campaign, use session notes, which the storyteller reads on every turn, up to 500 tokens.

Your character sheet as a persona and lore

A full character sheet is too long and too numeric to send with every reply, and most of it rarely matters. Split it:

• Who you are goes in a persona. Name, ancestry and class, background, personality, appearance, and goals. Save it under Personas in My Stuff and apply it from the Author drawer, and the storyteller reads it on every turn.
• What you can do goes in a short card. The numbers that come up in play: armor class, hit point maximum, key modifiers, proficiencies, spell slots, and signature features. Make it a lore card and pin it, or fold it into the persona if it’s brief.

A compact sheet the storyteller can actually use: “Wren, level 3 half-elf ranger. AC 15, 27 hit points. Dex +3, Wis +2, Con +2. Proficient in Stealth, Survival, and Perception. Longbow +5 to hit, 1d8+3 damage. Two first-level spell slots. Favored terrain: forest.”

Give companions their own lore cards with their names as tags, so the storyteller plays them consistently whenever they appear. When you level up, update the persona or the card, and mark the moment in the story so it lands in memory.

Dice: roll your own, or let the world roll

There are three honest ways to handle dice with an AI game master:

1. Roll real dice and report. Roll physical dice or a dice app, then write the result into your turn: “I loose an arrow at the ogre (rolled 14 + 5 = 19).” This is the most trustworthy method, and it keeps the thrill of the roll in your hands.
2. Let the Loom roll. LoreWeaver worlds can roll real random dice through the Loom, described below.
3. Ask the storyteller to roll. It works for low-stakes checks, but the number is written, not rolled, and it tends to favor drama. Don’t trust it with a character’s life.

The Loom is LoreWeaver’s no-code IF→THEN engine, and its threads can roll dice in standard notation: 1d20, 2d6+3, d100, or 4d6kH3 to keep the highest three. A Roll dice + check action compares the total to a DC you set, marks natural maximums and minimums as critical results, shows the roll on screen, can save the total and the outcome as world-state flags, and tells the storyteller what happened in your own words for success, failure, and criticals. A Dice check condition can gate a whole thread on a roll.

Be clear about what that automates and what it doesn’t. There is no built-in “/roll” command and no rules engine for your edition: a thread rolls when its conditions fire, and its DC is fixed. Threads suit recurring checks, such as a standard attack, picking locks, or a nightly encounter roll, better than every possible roll. A simple attack thread:

1. When the message starts with “/attack”.
2. Then roll dice + check: 1d20+5 against DC 13, labeled “Longbow”.
3. On success: “The arrow strikes home. Describe the wound and the ogre’s reaction.”
4. On failure: “The arrow goes wide, and the ogre closes the distance.”

The Loom guide walks through every condition and action.

Hit points, quests, and inventory on screen

The Loom also keeps the bookkeeping visible in the story’s HUD:

• Meters show a counter as a labeled bar, such as Health, Wounds, Supplies, or Reputation. Increment and decrement actions move them by set amounts, and a floor (zero by default) keeps them from dropping too far.
• Quest trackers open a quest with objectives, check objectives off, and mark it complete or failed.
• Inventory holds items with quantities and descriptions. Give, remove, and use actions change it, and threads can check whether you carry an item before a door opens or a ritual works.
• Achievements and hints mark milestones, and tappable choices offer options at a crossroads.

Because counters move by set steps, many solo players track exact hit points in their own turns (“I’m down to 9”) and use meters for states that change in steps, like exhaustion or a faction’s favor. World state follows the story: it lasts the whole session, a branch starts from the state at its fork, and a rewind or undo puts the flags back as they were.

Keep combat moving

Combat is where AI campaigns most often bog down. The fixes are the ones good human GMs use:

• Declare intent, then roll. “I shoulder-check the cultist off the ledge” gives the storyteller something to narrate, win or lose.
• One exchange per reply. Your action, the enemies’ answer, a decision. Long replies that resolve whole rounds take your choices away.
• Ask for enemies’ tells. Have the storyteller show who is wounded, who is wavering, and who is about to run.
• End fights early. Broken morale, surrenders, and retreats are more interesting than mopping up the last goblin. An OOC note does it: “(OOC: the rest flee. Skip to the looting.)”
• Keep positions in one line. A session note such as “Wren behind the cart; two goblins on the bridge; the shaman across the river” keeps theater of the mind consistent.
• Change pacing with presets. A preset with longer replies, such as Cinematic, suits a boss reveal; shorter replies keep a skirmish brisk.

Campaign memory across many sessions

A campaign is a long story, and long stories need memory. LoreWeaver keeps four kinds:

• Recent turns, word for word.
• Memories, written every few replies and found again by meaning and by the names and words they share with the moment.
• A running recap of the whole campaign so far, which you can read and edit.
• Lore cards for NPCs, places, and factions, which join a reply when their names come up.

Habits that keep a campaign coherent:

• Run the campaign in one session. Each session has its own memory bank. Keep playing the same one for months, branch it for what-ifs, and start a new session only for a new campaign. Lore cards belong to the world, so every session shares them.
• Card the recurring cast. When an NPC returns twice, give them a card with their name and nicknames as tags. On Plus and up, Emergent Lore Detection suggests cards for the characters and places the storyteller invents.
• End each sitting inside the story. A closing beat such as “We make camp below the pass. Tomorrow, Aldmere.” gives the memory writer a clean summary and you a clean restart.
• Review the recap between sittings. Add the open threads and fix anything it got wrong.
• Keep the quest log current. A Loom quest tracker or a line in your session notes tells the storyteller what you’re doing next.

Your plan sets how much of the campaign the storyteller can keep in view, from 6,400 tokens of context on the free plan up to 100,000 on Legendary, and paid plans keep more memories per story. How AI memory works explains the machinery, the AI dungeon master page shows the whole setup in action, and solo tabletop play walks through the workflow step by step.

Dungeons & Dragons and D&D are trademarks of Wizards of the Coast LLC. LoreWeaver isn’t affiliated with or endorsed by Wizards of the Coast, and the names are used here only to describe the game.