Wizarding World

Wizarding World is a tabletop role-playing game that is mechanically based on the Powered by the Apocalypse system and thematically based on the fictional universe of J. K. Rowling’s Harry Potter series. It draws inspiration from many previous attempts to build a Potterverse-themed game. It draws so heavily from materials like Dungeon World that you should really read to understand this. Perhaps I will eventually integrate the necessary materials.

I designed it for basic role-playing with my young kids. They are very interested in the Harry Potter world and in telling stories, but I wanted to give them some structure. Most of the other systems I’ve looked into attempts to create something like a traditional combat-focused RPG, which I don’t think works in the Potterverse. Or, they try to create something simulation-heavy, which isn’t right for my kids. I wanted something that was very light on rules and mechanics, but had structure to focus their creativity.

1 Basics

A play group is a gamemaster and multiple leads controlled by players. A lead is an important fictional character controlled by a human player. The gamemaster (or GM) controls the rest of the universe and adjudicates between leads.

2 Characters

2.1 Character Creation

Assign attribute modifiers: one is given a +2 modifier, one a +1, one a +0, and one a -1 modifier, representing a student’s initial endowment of ability. The relative values do not determine the house placement, which is purely determined by the fiction.

Choose one disadvantage based on the character’s identity. For example, Hermione is Mudblood, which makes some Pure Blood characters dislike her. She is also Oblivious, which gives her a disadvantage in some social situations. On the other hand, Harry is Ignorant of the Wizarding World, so he is disadvantaged in that area. Disadvantages do not apply specifically to one skill, but apply broadly to fictional circumstances.

Choose one advantage based on the character’s identity. This provides a relative +1 to any skill’s modifier. For instance, Neville has an advantage in Herbology, while Harry is advantaged in Defense Against the Dark Arts.

Set each other skill modifier at 0.

3 Skills

Other classes mentioned in the books are not skills and should be considered attribute actions or as their closest class, if they are ever arise in play. For example, Muggle Studies, Apparation, Arithmancy, Occlumency, Legilimency, Ancient Runes, etc.

3.1 Invoking Skills

Whenever a character attempts to invoke a skill, such as by casting a spell, remembering a piece of lore from a class, or using a divination technique, they must explain how they know about it. This may require a flashback-style scene where the player narrates what the class period was like when they learned about it.

If the characters are making plans, then it is best to resolve these scenes before getting into the action. For example, suppose Ron and Hermione are trying to ride a griffon as part of their plan, rather than interrupting that action later when they are wandering in the woods, resolve a class sequence early. This gives an opportunity for practice and, thus, advancement.

If the gamemaster knows a skill will come in handy later, they can put the characters into a scene as well. The players can also just ask for a scene from a particular class, which is a way of communicating to the gamemaster that they would like the solution to involve that class.

3.2 Spell Names

Whenever you cast a spell, wave your pencil around like it is a wand and say something that sounds Latin. Here’s a good way to generate fake Latin: think of a description of the effect in English, remove everything except nouns and adjectives (and sometimes verbs), then add Latin-sounding word endings, perhaps replacing old endings in the process:

Ron casts a spell to cause Malfoy to burp toads. We think, "Burp Toads from Mouth". Then, revise it to, "Toad Mouth". We come up with "Toadox Moutharum".

Harry protects himself with a charm that moves the air around him into a think fog to stop a piece of rock flying at him. We think, "Turn Air into Shield". Then, revise it to, "Air Shield". We come up with "Airae Shieles".

Each player may want to write down their own personal spell book on the back of their character sheet for consistency.

4 Advancement

Every skill and attribute (collectively called categories) has experience (or XP) points tracked for it. Every time a roll for a category fails, then the player marks an additional XP for it. This is called practice.

In between semesters, if a character’s skill’s XP equals 5, then they may undergo advancement and the modifier increases. A modifier cannot increase more than once a year. Modifiers may never increase beyond +3, except the initial advantaged skill.

For example, Harry fails a History of Magic at +1 roll attempting to do research on his own regarding the Triwizard Tournament and is disadvantaged in the game. He increments his XP on this skill and finally reaches 5 XP, so he may advance to +2 in the subject at the end of the semester.

This system encourages growth specifically in the areas where characters are not succeeding and rewards them with more options.

In the fiction, you can use modifier values as the student’s scores on tests, with +2 as passing O.W.L. with good marks and +3 as achieving N.E.W.T. status. Other than this, there is no purpose to explicitly representing tests, because it would be boring to have a student fail out of Hogwarts.

4.1 End of Session

For each "yes", then the character may mark XP in any category.

5 Actions

All actions use the basic mechanic. However, depending on the particular action the modifier is computed differently. Similarly, success and failure bring different consequences.

Each action’s modifier is computed by adding the disadvantage modifier (when appropriate), the year modifier, and either the attribute or skill modifier (depending on whether the action is a skill or general action).

The year modifier represents two ideas mechanically. First, young students are less capable of physical activities, are less convincing, astute socially, and so on. Thus, as they grow up, they become more capable generally. Second, for magical activities, the year modifier encodes the idea that Hogwarts is taking kids that have no skills in wizardry and turning them into proficient wizards.

It is generally obvious when and which skill is being used. Some subtlety comes from skills like History of Magic which is not explicitly a matter of casting spells with certain effects. I treat History of Magic as a stand-in for research in the library and remembering lore. Another complexity is whether knowledge of a particular magic creature comes from Care of Magical Creatures (for nice creatures, generally) or Defense Against the Dark Arts (for monsters, generally). In some circumstances, other skills may be appropriate, like a History of Magic for a creature of legend or Divination for centaurs. The most complex example, however, is when a spell is a Charm versus a Transfiguration. One changes what something does and the other changes what something is.

It is also generally obvious when some attribute applies, but less clear which one should apply. Most of my RPG experience comes from games like Dungeons and Dragons and Dungeon World, so I try understand the attributes relative to those games. I treat Gryffindor as a combination of STR, WIS and a little CON; Hufflepuff as WIS, CON, and a little CHA; Ravenclaw as INT and DEX; and, Slytherin as DEX, INT, and a little CHA.

5.1 Attribute Examples

Luna sneaks down the hallway to avoid being spotted by Mrs Norris... Ravenclaw, because it is a matter of intelligence and grace.

Malfoy comes up with a rumor to raise suspicions of Harry... Slytherin, because he is trying to be cunning and manipulative.

Harry tries to convince Neville to help him on his Herbology task... Slytherin if he is being manipulative and Hufflepuff if he is being kind and loving.

Neville runs straight at Voldemort even though he is readying a curse... Gryffindor, because he is demonstrating bravery.

Hermione works on fixing the magical artifact damaged by a misfired curse... Hufflepuff, because she is exerting hard work and effort to figure it out. If instead she had investigated in the library for a way to fix it, perhaps it would be a History of Magic skill.

Ron is trying to understanding what happened in this room to cause such a mess... Ravenclaw, because it is a matter of intelligence, reasoning, and attention to detail.

5.2 Combat

Combat is not a separate kind of activity from the rest of play, but follows the rest of the structure of play.

Characters in the Potterverse are very brittle and the style of story does not lend itself to dungeon crawls with many monster falling by the sword. Most duels are ended in just a few spells. This is reflected in Wizarding World with the Status system.

Impeded normally involves something physical, like being de-wanded or losing your glasses, while Cursed normally involves something magical. A character is typically only Hexed as a consequence of the plot and not as a normal course of events.

A typical duel involves trying to get your opponent Cursed and then moving in for two Hurts to bring them to Taken Out.

5.3 Consequences

As a result of an action, there may be positive or negative consequences. In general, these should always flow from the fiction. The story is most interesting when the leads don’t get their way exactly. So, on a success, the gamemaster should look for a way to give the player a hard choice of two good things out of three possibilities, while on a partial success, they can only choose one.

For example, if Snape is attempting to de-curse Harry’s broom without being noticed, his goal is to (a) cast the spell effectively, (b) not be noticed, and (c) not have a counter-curse put on him. In the actual story, he chooses to not get result (b), as Hermione notices him.

Here are some choices that may be appropriate in different circumstances.

• You hurt, curse, or impede the target.

• They don’t successfully hurt, curse, or impede you back.

• You don’t attract attention.

• The immediate threat is averted or driven off.

• The person you were rescuing is unhurt.

• The people you don’t want to find out don’t.

• The rumors paint you in a positive light.

• The event you were trying to stop is only weakened.

• You haven’t left yourself or whoever you were helping open to a follow-up.

• There isn’t an unexpected side-effect.

• You can ask the GM to truthfully answer a question.

• You heal or bless without any negative side-effect.

• They agree to what you want them to do.

• No one finds out what you did.

• You understand what to do without acting dangerously.

• You don’t leave something important behind.

• You don’t expose yourself to risk or cost.

Here are some ideas for consequences:

• Take things in the worst possible way.

• Take things to the logical extreme.

• Add a strange magical effect.

• Split the players up.

• Bring someone new into the scene.

• Give them a choice of the consequences.

• Hurt them, hopefully in a ridiculous way.

• Put them in the wrong place at the wrong time.

• Introduce a magical event.

• Have a ghost or creature do something strange.

• Have someone act without thinking.

• Make their action work, but turn it around them on.

There are no strict rules for what are consequences. The only principle is that: on a success, you get what you want with only soft consequences; on a partial, you get most of what you want with maybe a hard consequence; and on a failure, you don’t get what you want and experience hard consequences.

6 Miscellaneous

6.1 Quidditch

I don’t like Quidditch, so I don’t include it in the game mechanically.

6.2 Probabilities

The following tables show the probability of succeeding in various circumstances:

This essentially shows that first years are extremely unlikely to succeed in anything: their +2 attribute only gives them a 36% partial success rate and their advantage (+1) skill gives them only a 28% chance. Complete successes are even lower with rates of 8% and 3% respectively.

On the other hand, seventh years are very capable, but not invincible, even in their advantage at N.E.W.T. levels.

6.3 Advancement Difficulty

Advancement through practice is increasingly more difficult, because it relies on repeated failure to accumulate XP. Essentially, the probability of advancement is a negative binomial random variable where r is 5.

Thus, in the first year, the expected number of spell attempts to advance a normal skill is 7. If we assume this happens in the first year, then it will take 9 attempts to advance again in the second year and 18 attempts to finish advancing in the third year. These are very large numbers if you consider there being about five or six scenes per semester. The character would be practicing the same skill in every scene.

Alternatively, we could imagine it will take two years for each advancement and average the number of attempts per year. This would require 7 attempts by the end of second year, 16 attempts by fourth year, and 60 attempts by the end of sixth year.

In summary, this essentially means that an excellent witch will only be a +2 by the end of fourth year in most subjects, except their specialty which may be +3, with the rest of advancement coming through role-playing.

7 Gamemastering

Follow all the advice of Dungeon World. The gamemaster never rolls dice for mechanical ends (although you may want to use them for randomization purposes.)

Any time you give a consequence, make it something the players won’t like. Whenever a player does something thoughtless, give them another one.

Turn simple things into big ordeals. For example, if the leads want to make a potion, don’t just make a Potions roll. First, make them trick a teacher into giving them access to the recipe or materials. Then, they have to sneak around to get them and assemble the potion in secret. They have to make the skill action to make it properly, but they have to be brave to actually quaff it, and if they aren’t brave enough, maybe someone walks in because they were delaying before doing it.

7.1 Story Advice

Your style and taste may vary, of course. With my kids, I take the kids from first-year through seventh-year, stop, and then start again as new students as if the universe reset. I do not use any characters from the actual Potterverse, because I want things to be as mysterious and open as the books were. I try not to use stand-ins for them either, so there is no character that is like The Boy Who Lived or He Who Must Not Be Named. Nevertheless, there are still dangerous people and mysterious artifacts around Hogwarts that attract the attention of dark wizards.

The general flow, that comes from the book, is to have each year divided into before and after Christmas break, where beforehand the characters interact with both the Year Front and Mystery Front, but cannot discern which one they are interacting with. Around the break, they are almost resolved with the Mystery Front and understanding that the Year Front is a separate concern. These are then resolved in sequence after break.

Since I’m running this for my small kids, I don’t deal with any of the teenage angst of the books or give any real opportunity for darkness, because that’s not my taste, so you won’t see much recommendation for that in here.

8 Resources

9 Acknowledgments