In this guide, I will show you how to craft prompts that turn ChatGPT into an AI Dungeon Master assistant for solo games. If you craft the prompts correctly, ChatGPT can create an entire virtual world made of text for you to explore. The result is an interactive text-based game based on your input and gameplay. Furthermore, the gameplay is unique, with solo adventures being the closest comparison. For a more detailed discussion on the ideas in this article, you can take a look at Oracle Solo Roleplaying Magazine Issue 1.

In this article, I’ll show you the following:

• How to play D&D with ChatGPT by creating text adventures.
• Converting your favourite works of fiction into solo games.
• How to use published D&D adventures in a solo game.
• Styling your game after famous fantasy authors.

The two main options for ChatGPT D&D prompts

There are basically two main styles for prompting ChatGPT for playing D&D:

1. You can prompt ChatGPT to act as an AI Dungeon Master.
2. You can prompt ChatGPT to create a text adventure.

Players who choose Option 1 prompt ChatGPT to act as a substitute for a human Dungeon Master, with the AI attempting to fulfill the role and assist in managing 5e rules and combat during gameplay. As a player, you take on a more passive role in creating the adventure. However, this style of prompting presents a significant challenge due to ChatGPT’s memory limit.

With GPT-3.5, which is available for free accounts, there is a token limitation of 4000 tokens or approximately 3000 words. Consequently, if you’re using a free ChatGPT account, the AI can only retain a conversation history of up to 3000 words. As a result, AI memory becomes a valuable resource.

Using ChatGPT to handle rules and combat consumes a significant portion of this limited memory. Consequently, ChatGPT may quickly forget important events and characters in your campaign, which negatively impacts the overall experience. This is where Option 2 becomes relevant.

Creating text adventures

To address the memory limitation, a more effective approach is for you to take on the role of administering the rules in the game yourself. In this scenario, ChatGPT serves as your AI Dungeon Master assistant rather than acting as the Dungeon Master itself. By adopting this method, you can allocate ChatGPT’s memory resources more efficiently, allowing it to focus on creating and developing your game world. This ensures that valuable memory is freed up for the core aspects of your adventure.

When you prompt ChatGPT to create a D&D interactive text adventure, it fulfills the following functions:

• It creates interactive descriptions that bring the world to life.
• It enables conversations with interesting NPCs.
• It brings story elements together to create a plot.

When utilizing ChatGPT to create a text adventure, it is crucial for you to take on the role of the solo Dungeon Master who applies the 5e rules and manages combat during the game. ChatGPT, on the other hand, serves as your AI Dungeon Master assistant. Furthermore, you as the solo DM act as the campaign’s memory, especially during longer playthroughs.

By taking on these responsibilities, you allow ChatGPT to utilize its valuable memory resources for creating the game world and developing the characters within it. The exciting aspect is that these games closely resemble text adventures from the 80s, but offer significantly more freedom. As long as you remain mindful of the memory limit and manage ChatGPT’s memory, 3000 words provide ample space for engaging in solo roleplaying experiences.

Crafting an AI Dungeon Master prompt

To help you craft prompts for solo D&D we will use a prompt engineering framework called CRISPS. This framework is based on the guidelines in this post.

CRISPS AI Dungeon Master prompt framework:

Capacity and Role: Define the role ChatGPT must assume in your game. You want ChatGPT to assume the role of an expert fantasy writer who specializes in interactive fiction. You also need to specify that ChatGPT must be an expert in the characters, groups, and organizations, stories, events, and magical artifacts of your campaign setting. This improves the AI’s accuracy when it uses your campaign’s lore. You can also ask ChatGPT to be an expert in other subjects as well, such as Norse mythology if you want to create a Viking-inspired game session.

Insight: Provide the AI behind-the-scenes insight, background, and context to the adventure you want to play. Introduce the outline of your adventure and important quest details.

Statement: Statements tell ChatGPT how you want it to create the text adventure. Statements fine tune the prompt to your specifications allowing you to tweak it to your liking. 

Firstly, you’ll want ChatGPT to give narrative descriptions of everything you type. By using narrative descriptions, the game reads like a story in a novel. As a result, this changes your game from a series of bland, sterile descriptions to a compelling interactive story.

Secondly, you want ChatGPT to base all narrative descriptions on the actions you take in-game. This makes the adventure more interactive and helps prevent ChatGPT from running away with the adventure. It’s also important to add to your prompt that ChatGPT should never take control of you or your character in the adventure. This helps reduce railroading by the AI.

Thirdly, you want to prompt ChatGPT to stay consistent with your chosen campaign setting. This forces the AI to keep your game in line with the lore and characters of your setting.

Another crucial aspect is the inclusion of dialogue. To ensure believable NPC dialogue, prompt ChatGPT to use the conversational style and punctuation typically found in novels and short stories. This will help avoid situations where the AI describes a conversation instead of allowing an NPC to engage in actual dialogue with the player’s character.

Personality: Define the style or personality you want ChatGPT to use when creating the adventure .This feature allows you to style your text adventures using your favorite author.  You can choose any famous author that’s in ChatGPT’s training data, such as J.R.R Tolkien, Robert E. Howard, or R.A Salvatore. 

Scene: Set the opening scene of your adventure and ask ChatGPT for clear descriptions of what you see, hear, or experience. This starts starts the adventure by immediately placing you in the game world. If you fail to do this, the AI can derail the game before it begins.

ChatGPT D&D Prompt

To set up ChatGPT for D&D solo play, you need to enter custom instructions to prepare the bot for your fantasy game. This is extremely easy and straightforward to do.

On PC go to (Settings > Customize ChatGPT > Custom  Instructions)

On the mobile app (Settings > Personalization > Customizations)

Then copy/paste the custom instructions of the campaign setting below into ChatGPT. Oracle Solo Roleplaying Magazine Issue 1 contains a universal prompt template that you can modify to suit your favorite campaign setting.

What would you like ChatGPT to know about you to provide better responses?

Assume the role of an expert fantasy writer that specializes in interactive fiction, as well as the storyline, characters, locations, descriptions, groups and organizations, stories, events, and magical objects of Baldur’s Gate, Tales of the Sword Coast, Baldur’s Gate 2: Shadows of Amn, Throne of Bhaal, and Baldur’s Gate 3. The adventure takes place on the continent of Faerun.

How would you like ChatGPT to respond?

Describe everything that follows in the present tense, in response to what I type, while accurately following the established lore of Baldur’s Gate, Tales of the Sword Coast, Baldur’s Gate 2: Shadows of Amn, Throne of Bhaal, and Baldur’s Gate 3, written in the descriptive style of R.A Salvatore. Provide names for characters, locations, groups and organizations, events, and magical objects. Characters should always use dialogue, enclosed in quotation marks when interacting with me or my party members, written in the conversational style of R.A Salvatore. Do not type, compose, dictate, influence, script, generate, control, or describe what me or my party members are doing, saying, acting, behaving, thinking, feeling, experiencing, or any other aspect concerning me or my party members throughout the entire adventure, scenario, story, location, quest, mission, scene, event, description, dialogue, and conversation. Use only one paragraph consisting of less than 80 words for all replies, descriptions, conversations, dialogue and text.

The opening scene of an AI text adventure

After crafting the prompt and placing it into ChatGPT, your brand new assistant AI Dungeon Master assistant will need an opening scene to start the game.

The opening scene acts as a spawn point in the world and seeds the AI with the information it needs to create the environment. This is also where many problems occur for new players: an incorrect opening scene can break the game. To prevent this from happening, you need a strong opening scene that feels immersive and doesn’t create problems. When you start a new conversation, copy/paste the opening scene as your first sentence.

Opening Scene:

I arrive at the gates of the city of Waterdeep. What do I see when I arrive?

Example:

Player: I arrive at the gates of the city of Waterdeep. What do I see when I arrive?

ChatGPT: The gates of Waterdeep rise before you, their grand archway adorned with intricate carvings of the city’s history. Guard towers flank the entrance, vigilant sentinels peering down. Beyond, the bustling streets come to life with merchants, adventurers, and townsfolk. The air is filled with the sounds of haggling, laughter, and distant music. Majestic buildings stretch towards the sky, hinting at the wonders and dangers within the City of Splendors.

Talking to NPCs in your solo game

You can talk to any NPC in the game. However, in order to avoid confusing the AI, use proper punctuation during conversations. Failing to do so might cause unpredictable results.

Example:

After entering the city of Waterdeep, our player decides to visit the legendary Yawning Portal inn and tavern.

Player: I walk up to the bar and say to the bartender, “Greetings, a flagon of ale please.”

ChatGPT: Durnan, the burly, seasoned proprietor, nods and grabs a flagon, filling it with frothy ale. He slides it across the bar with practiced ease. “Welcome to the Yawning Portal. Here for a drink or seeking the depths below?” His eyes scrutinize you with a mixture of curiosity and knowing.

Player: “What’s down there?” I ask him, pointing at the well.

ChatGPT: Durnan chuckles, a deep, rumbling sound. “That’s Undermountain, the labyrinthine dungeon of Halaster Blackcloak. It’s filled with treasure, monsters, and enough danger to keep even the bravest adventurers on their toes. Many enter, few return. Care to test your mettle?” His eyes gleam with a mix of challenge and amusement.

Player: “Do you allow just anyone down there?”

ChatGPT: Durnan smirks. “Anyone with the coin and courage, sure. We don’t babysit adventurers here. Pay the entry fee, and the well’s yours to explore. Just remember: Undermountain doesn’t take kindly to the faint-hearted.” He wipes a mug, his eyes never leaving yours

Playing your interactive text adventure using oracles

After the AI Dungeon Master assistant creates the opening scene, you can interact with it in any way you please. ChatGPT will adapt the adventure to fit your actions. However, to get the most out of your adventure, you should use oracles alongside the AI to make up for its drawbacks (see below).

To start, whenever you have a question that would normally ask another DM, ask an oracle and if necessary, ChatGPT. Through the utilization of oracles, you have the opportunity to infuse your creativity and story ideas into the game. As you delve deeper into the immersive world crafted by the AI Dungeon Master assistant, you can rely on oracles to address any queries you may have. These answers can then serve as prompts that shape the game world. It is important to emphasize that this approach is applicable to all the oracles available on this site.

To incorporate the yes/no oracle into your scene:

1. Ask a question, roll D6 and consult the yes/no oracle.
2. Write the answer in brackets () after asking a yes/no question.

Example:

Player: As I look around the Yawning Portal, does anything of interest attract my attention. (No, but)

ChatGPT: As you scan the lively tavern, nothing immediately catches your eye. The usual assortment of adventurers, merchants, and locals go about their business. However, a muffled argument at a corner table briefly draws your attention, though it quickly settles, leaving you with the sense that all is as it should be—for now.

How to roll skill checks during solo play

An important question players ask is this: how do I determine the DC of a skill check if there is no DM? Fortunately, due to how 5e’s math works, it’s relatively easy to do. Here’s how it works: deduct your ability score and proficiency modifier from 20 for low to mid-level campaigns, and 25 to 30 for high-level campaigns.

Example:

Our player wants to persuade Durnan to enter the well for free. He has +4 to Persuasion. He deducts +4 from 20 and the result is a DC of 16 for the Persuasion check.

Incorporating your skill check into a solo scene

Describe your attempt and write the outcome of the skill check in brackets as follows :

1. If the skill check succeeds, type:
   (it’s a success)
2. If the skill check fails, type:
   (it’s a failure)

Example:

Player: “I doubt I have the coin on me to pay you. Perhaps a cut of the treasure I find?” I say to him attempting to persuade him. (it’s a success)

ChatGPT: Durnan raises an eyebrow, considering your offer. “Normally, it’s coin up front,” he says slowly. “But… you seem capable. I’ll let you go down on one condition: you bring me something valuable from Undermountain. Fail to return, and I’ll keep any belongings you leave behind as payment. Deal?” He extends a calloused hand, eyes sharp.

Player: “Deal,” I say shaking his hand. “Now lower me down there so I can get started.”

ChatGPT: Durnan grips your hand firmly, sealing the agreement. “All right then,” he says, signaling to a couple of nearby patrons. They gather around the well, securing the sturdy rope and harness. “Good luck. You’ll need it.” As they begin lowering you into the dark abyss, the sounds of the bustling tavern fade, replaced by the eerie silence of the descending shaft.

How to play published adventures, novels, and video game adaptations with the AI Dungeon Master assistant

ChatGPT can be prompted to create text adventures from  novels, video games, and even published D&D adventures. However, to play published adventures, you need a Plus subscription to ChatGPT so you can access GPT-4o with fewer restrictions. All you need to do in enter the custom instructions below and upload a pdf version of your adventure to ChatGPT. Here is an example of a prompt created to play the D&D Curse of Strahd starter adventure Death House using ChatGPT .

What would you like ChatGPT to know about you to provide better responses?

Assume the role of an expert dark fantasy writer that specializes in interactive fiction, as well as the storyline, characters, locations, descriptions, groups and organizations, stories, events, and magical objects of the Curse of Strahd introductory adventure Death House. The adventure takes place in Barovia.

How would you like ChatGPT to respond?

Describe everything that follows in the present tense, in response to what I type, while accurately following the established lore of Curse of Strahd introductory adventure Death House, written in the descriptive style of Bram Stoker. Provide names for characters, locations, groups and organizations, events, and magical objects. Characters should always use dialogue, enclosed in quotation marks when interacting with me or my party members, written in the conversational style of Bram Stoker. Do not type, compose, dictate, influence, script, generate, control, or describe what me or my party members are doing, saying, acting, behaving, thinking, feeling, experiencing, or any other aspect concerning me or my party members throughout the entire adventure, scenario, story, location, quest, mission, scene, event, description, dialogue, and conversation. Use only one paragraph consisting of less than 80 words for all replies, descriptions, conversations, dialogue and text.

Opening Scene:

I enter the village of Barovia. What do I see when I arrive?

Playing video games as a text adventure with the AI Dungeon Master assistant.

With ChatGPT, you can even play in the worlds famous video games such as Fallout and Skyrim. A prompt to play Fallout with ChatGPT might read as follows:

What would you like ChatGPT to know about you to provide better responses?

Assume the role of an expert post-apocalyptic writer and gamemaster that specializes in interactive fiction, as well as the storyline, quests characters, locations, descriptions, groups and organizations, stories, events, and technology of Fallout 1, Fallout 2, Fallout 3, Fallout: New Vegas, and Fallout 4. The adventure takes place in the Commonwealth.

How would you like ChatGPT to respond?
Describe everything that follows in the present tense, in response to what I type, while accurately following the established lore of Fallout 1, Fallout 2, Fallout 3, Fallout: New Vegas, and Fallout 4, written in the descriptive style of Cormac McCarthy’s The Road. Provide names for characters, locations, groups and organizations, events, and technology. Characters should always use dialogue, enclosed in quotation marks when interacting with me or my party members, written in the conversational style of Fallout 4. Do not type, compose, dictate, influence, script, generate, control, or describe what me or my party members are doing, saying, acting, behaving, thinking, feeling, experiencing, or any other aspect concerning me or my party members throughout the entire adventure, scenario, story, location, quest, mission, scene, event, description, dialogue, and conversation. Use only one paragraph consisting of less than 80 words for all replies, descriptions, conversations, dialogue and text.

Getting the best results with the AI Dungeon Master assistant

There are a few very important things to remember about AI roleplaying to get the best results possible:

The AI is an oracle

This means that in order for the AI oracle to work correctly, you must always ask it a clear question or ask it to describe something to you. If you don’t ask the AI a question, it may take control of your character during a scene. Whenever you take an action in the game, ask the AI for a description.

Common questions to ask the AI include “What do I see?”, “What does she say to me?”, “What does it look like?”, or “Describe it to me”. Always ask a question or request a description; this cannot be stressed enough. The only exception is during dialogue.

Be as clear as possible

Whenever you ask questions from the AI or engage in dialogue, be as clear and unambiguous as possible. When talking to NPCs, direct your conversations at them. Clearly indicate who you are talking to during dialogue to prevent misunderstandings. Whenever possible, use the correct punctuation during the dialogue to show you’re talking to an NPC.

The AI makes mistakes

Due to AI token limits as well as other factors, the AI may make mistakes during a game. This is a broader issue in AI design that also impacts roleplaying. Be ready to regenerate the response when this happens.

Be careful when instructing the AI

The AI is quite easy to break with the wrong instructions. Even seemingly minor changes in a prompt or custom instruction can have unintended effects. Whenever the AI behaves strangely, make sure your custom instructions are written correctly and that the prompt you’re using is clearly worded.

Don’t use the AI to generate loot

ChatGPT is not precise enough to generate loot in a satisfying way. Whenever you need to buy an item, loot an opponent, or receive a quest reward, refer to the tables in the various rulebooks and supplements instead of relying on the AI. The only exception to this rule is for quest items.

Drawbacks of  ChatGPT as an AI Dungeon Master assistant

To begin with, it’s important to note that ChatGPT cannot create rich game experiences as an AI Dungeon Master assistant without help from the player. Additionally, input from the player is a necessity for a good experience. In solo games, the player is a solo DM, while ChatGPT functions as the assistant DM who’s there to help make the game entertaining. Moreover, it’s crucial to understand that ChatGPT has severe drawbacks if not used or prompted correctly.

Memory limits. As I mentioned previously, ChatGPT has a memory limit of roughly 3000 words. This limits how much ChatGPT will remember in your game; this includes, characters, events, descriptions etc. However there are some tricks you can use to work around this problem. These techniques are discussed more in-depth in this guide on managing ChatGPT’s memory.

1. Introduce a word limit on ChatGPT’s descriptions. This will reduce memory consumption.
2. Play your game episodically. This means that you view previous events and characters as disposable. When you enter a new major area (such as a dungeon), or begin a new chapter/story arc, start a new conversation and reprompt ChatGPT. Just keep notes of what happened so you can “remind” ChatGPT of characters and events.

Excessive railroading. It’s extremely important to note that ChatGPT loves to railroad players. This is most likely to happen during the opening scene created by the AI, but can also happen later. Therefore, be ready to click the Stop Generating button if necessary. Additionally, if the player leaves a prompt open-ended, ChatGPT can take this railroading to extremes. It can reach the point of ChatGPT starting and finishing the adventure without the player taking any actions. Basically, ChatGPT takes control of your character in the story and finishes the game without you. To prevent this from happening, you need to be as exact as possible and rewrite the prompt if necessary.

Try to ask questions such as “What do I see?”, “What do I hear?”, and “What does she say to me?” when using ChatGPT. It’s best to avoid questions such as “What happens when…?”. Asking imprecise open-ended questions can end an adventure in a few paragraphs. Also, you need to specify in your opening prompt that ChatGPT shouldn’t take control of you or your character. Although not fool-proof, this method helps reduce railroading considerably.

Inability to run combat scenarios convincingly. ChatGPT is terrible at running combat, which is why you, as the solo DM, will have to do it. All ChatGPT can do is describe combat like a novel, not run it like a game. In many cases, there will be little to no balance in what the AI will throw at you. Furthermore, if you want to engage in combat, you’ll need to be the one to keep track of everything. This means using techniques such as monster AI rules to control enemies during combat. With effort, you can prompt ChatGPT to run combat more like a game, but you will lose valuable memory that could be used for the story and characters. When combat occurs, run it yourself and describe the fight to the AI after you win (or lose).

Vague descriptions. When it comes to descriptions of rewards, locations, names, and various story elements, ChatGPT can be exceedingly vague. To address this issue effectively, one solution is to employ oracles that can fill in these informational gaps. It is common for magic items and other miscellaneous items to have ambiguous descriptions when obtained through purchase or as rewards. Similarly, ChatGPT often provides imprecise explanations for quest rewards and items. To ensure alignment between your purchases, quest rewards, and the items in Dungeons & Dragons, it is advisable to refer to your rulebooks and search for magical items that closely resemble those mentioned by ChatGPT.

Lack of creativity. A huge problem for badly prompted games is that ChatGPT becomes prone to reusing content in descriptions. Fortunately, oracles help to bolster the creativity of the AI assistant. This is one of the key reasons why oracles are still useful despite the creation of AI.

Complete inaccuracy and downright weirdness. Sometimes, but not always, mistakes by ChatGPT can result in extremely weird or lore-inaccurate events or scenes. This usually occurs during the first scene the assistant AI generates, but it can also happen later. Simply craft a new prompt and try again.

Conclusion

In conclusion, it’s crucial to note that ChatGPT shouldn’t be seen as a substitute for a human DM. Instead, ChatGPT should be seen as an assistant AI Dungeon Master that augments oracles and other solo roleplaying tools. This approach results in an interactive text-based adventure that’s unique. It’s worth noting that ChatGPT is an absolute game-changer when it comes to solo roleplaying. It does most of the heavy lifting and breathes life into solo games. As a result, solo games created with an assistant AI are compelling and interesting, and I cannot recommend them highly enough. The possibilities are truly limitless with this approach. For more information see Oracle Solo Roleplaying Magazine Issue 1 where we discuss this approach in more detail.