Rules for the GM

Creating and Running Adventures

Mirage is a long-form improv game. Your goal is to create a fun story together with your players.

To play the game you need an adventure. Make up your own, or use a premade one. Find a collection of premade adventures here. Join our Adventure Writer’s Room - a community of GMs who meet in the discord voice chat, and improvise adventures together. You can follow our brainstorming process to make up adventures on your own as well. See a useful guide on making adventures here.

Before the game - help the players to understand the rules and create their characters.

During the game you tell players what’s going on around them, ask them what they want to do, and then use your imagination and results of dice rolls to describe consequences.

Give the players a task to accomplish (find the treasure, defeat a monster, save the princess). Put challenges on their path, obstacles to getting what they want. Watch them find creative ways to overcome them. 

Imagine how the world responds to their actions, create and describe interesting consequences, add fun complications. Play the role of all NPCs like an actor, respond to what the players do the way these characters would respond.

Don’t over-prepare, don’t try to force preplanned outcomes. Play to find out what happens. “Yes And” players’ ideas - let them take the story in their own direction, then build on top of their ideas.

Bring the story to an awesome, dramatic, satisfying conclusion. Like an epic climactic showdown with the antagonist. Watch the heroes overcome their biggest challenge and reach their goal.

Rolling Dice

Tell the players to roll the dice only when both succeeding and failing at the action could each contribute something interesting to the game. The situation always changes after a roll, for good or ill, each outcome pushes the story forward. If the failure doesn’t lead to interesting consequences (“nothing happens”) - don’t call for a roll, just make the judgement yourself. 

Before the roll, set the target number the player needs to beat in order to succeed at a task. Make it higher or lower depending on the difficulty of the task.
5 is easy, 10 is average, 15 is challenging, 19 is very hard.

If the player fails at a roll - you can offer them to reroll the dice at the cost of suffering some negative consequence/complication/setback (take damage, lose an item, lose time, attract unwanted attention, give the enemies an opportunity to advance, cause collateral damage, etc.), or taking a riskier option.

When the player uses a talent relevant to the task they’re attempting, comes up with an awesome creative idea, or has an amazing roleplaying moment - tell them to roll with advantage.

Split interesting tasks into several rolls, resolve simple tasks in one (Picking a lock is a single roll. To open a bank vault you might want to roll for disabling the alarm, breaking the lock, hiding from the guard patrol.)

Don’t call for a roll just to see if a spell or an attack fails. In combat, the weapons deal static damage and hit automatically, so rolling dice every turn isn’t necessary. Call for a die roll only when there’s a reason the attack would be extra difficult or risky, or when it’s interesting to have an unpredictable outcome.

The spells never fail to work. Outcomes and results may depend on a roll, but if the player casts a spell, the spell is going to go off and do what it’s description says.

Don’t hide information behind the roll. If the player describes looking for clues - they find them.


Use your judgment and common sense to decide what happens as the result of players’ actions. If you were watching a movie, and a character had tried to do what the player wants to attempt, what do you think would happen?

Follow the rule of cool. The more awesome, creative, or funny the player’s idea is, the more likely it is to work.

Don’t be afraid to add complications, unexpected negative consequences, tension, drama - it’s good for the story (“You have successfully killed the guard, but someone has seen it and is now running to raise the alarm.”)

Awarding Vitality Tokens

Award VT when the player uses their trait to make the story more interesting and exciting. You’re free to decide whether the player’s action earns them VT.

When you see an opportunity for the player to use one of their traits - suggest it to them (“You see someone in danger. If you risk your life to help them, you will gain 3VT.”) 

If you want players to have more VT to play with - award it for awesome ideas, jokes, roleplaying moments. Or just let them find a Vitality Potion.

Awarding Abilities and Items

At the end of the session give each player something cool as a reward. Give Nifty items to novice characters, give more powerful ones after they are a bit more advanced.

Give Supreme powers on special occasions, at major story milestones. Make receiving the Supreme power a part of the story, a meaningful and exciting moment in the adventure.

Creating NPCs

Create NPCs the same way players create characters. Select a few abilities and items, come up with a name and a description.

NPCs don’t use traits to recover VT. Give them more or less VT based on how powerful you want them to be.

Friendly NPCs can offer to trade their items with players, or give them as a reward for completing quests.

Important enemy NPCs can be looted after they’re defeated, each player gets one of the items they’ve had.

Use the NPCs App to prepare your NPCs. Hover over “Create” button and choose a premade NPC to get started with. Add an image, fill in the description. Click on the stats button (top-right corner of the NPC card), and customize their powers, items, and stats.

Running Combat

During the action scenes, players take turns describing what they do, then you take a turn for every NPC.

During their turn, they can move and take one action (attack, cast a spell, drink a potion, etc).

You can also play without the turn order, if that’s more convenient. Call on players when it makes the most sense for their characters to take action (but try to make sure that players get roughly the same amount of screen time).

You don’t have to run combat blow-by-blow if it doesn’t feel dramatically interesting and entertaining. You can resolve the whole fight in one roll, or in multiple stages - each roll is for a decisive moment in the conflict, not an individual action. Ask the players how they want to fight, roll to see who wins, narrate the result. If the players lose - they can end up in a more difficult situation, lose VT, or be at the mercy of their enemies.

Custom Powers

Encourage the players to invent their own traits, talents, abilities, and items. Brainstorm them together. Make sure that abilities/items aren’t too game-breakingly overpowered. Make sure that traits create right incentives, encourage players to do things you want to see in the game.

Rule Zero

All these rules are only a guideline, they exist to help you have fun and tell a cool story. If a rule stands in the way of playing the game you enjoy - ignore it or change it. You are free to override any of the rules, to simplify or extend this system. If there’s any confusion about the rules - don’t waste time arguing about them or looking things up. Make the decision that makes the most sense to you and go with it.

We’re looking for the GMs!

If you’re interested in running a lighthearted, low-combat, storytelling/improv-focused one-shot in Mirage (or know a GM who might be) - join our discord server and send me a message! (I’m lumen#7925)

A few notes:

  • Mirage isn’t meant for combat-heavy games, and probably won’t work great for those. It’s designed with storytelling/improv in mind, so it’s for people who like that kind of stuff.
  • It’d be ideal if I could find people willing to run one-shots, as opposed to long-term campaigns. That way more people on the server would get to play games from time to time, instead of one consistent group with consistent schedule.
  • If the rules for GMs are still a bit unclear/confusing, if you have any questions, or are having trouble preparing an adventure - I’ll be happy to help! Message me in discord and we’ll figure it out.
  • It’s best if you first participate in a few games as a player, to get a better idea of how things works.
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