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HAT, or HP - AC - TWENTY SIDED, is a roleplaying game that shares three basic concepts with D&D but diverges from there. The three concepts kept from D&D are obvious from the title: HP, AC, and the D20 roll. However, each is expanded in scope. One of the goals of HAT is to create a game that embraces a more narrative and situation driven feel, while maintaining support for classic D&D modules. This is the first version on these rules, known affectionately by the author as the Bowler edition.
This page introduces and defines all the terms used in the game. It is a large, functional part of the rules as they are presented online. Many other pages link into this one in order to prevent redefining the same terms and rules over and over.
We divide these term into three groups: Core Terms, Standard Terms, and Optional Terms. Core terms are things needed to understand and play the game, all players should have a rough idea of how they work. Standard terms are basic parts of the game, but may or may not apply to all players. They just need to learn the terms that apply to their characters. Optional terms are ones that appear in optional rules for play, and may or may not be used in any given game of HAT.
One basic concept is at the root of all play though, so lets get that out of the way:
Characters are a collection of traits, each of these a word or phrase that says something about the character themselves. For example, Strength, Blitz, and Dwarf are all traits. Each trait is defined by its type and substance. The type is always one of the following: Attribute, Ability, or Aspect. The substance is how the trait works in the rules. Adjectives, Clauses, Modifiers, and Usurp are types of substance.
Traits can't possibly describe everything about a character. We solve this by using the rule of assumption. Assumption is a process by which we assume a character has quality X if no trait sets that quality. Here are the qualities which are handled by assumption:
Here are the terms used most in the game, the basic concepts of HAT.
One of the three types of Traits. These are the most specific of traits, meaning they are narrow in application. The question of whether an Ability applies to a situation is totally in the hands of the GM. Each ability has Adjectives and Clauses for its substance. There is a set of many Standard Abilities in HAT available for use, our you can construct them using the Ability Construction Set.
One of the three types of Traits. These are gross traits that describe the character in general. While there are special ones, and they can be created by the player, there is a basic set: Strength, Constitution, Dexterity, Intelligence, Wisdom, and Charisma. Each attribute has a Modifier and Adjectives as its substance. Since a modifier can be a boon or a hindrance, you can't assume that a character with an attribute has it as a virtue. It could also be a flaw.
One of the three types of Traits. Things that aren't specific like Abilities, or gross traits like Attributes, fall into the category of Aspects. This means it ends up as a sort of catch-all for traits that don't fit into either of the other two categories. Aspects include things like character Histories, Natures, Beliefs, Legends, and so on. You can create your own Aspects with the help of the GM (see Authoring), or use any from the Known Aspects list on this page. Aspects have a special type of substance called Usurp meaning when they apply you work with the GM (without rolling) to see how they impact the fiction.
One of the substance rules for traits. Adjectives in HAT are free-form, and floating words or phrases that impart value. Each has no set target, hence: floating, and each can be created freely by players, hence: free-form. Adjectives impart value and as such denote a form of capability. Let us explore an example. During Adventurer creation you take the Attribute: Dexterity. It says under Dexterity to pick on Adjective. What you do now is decide what Adjective you want that might describe your Adventurer's nimble nature or their prowess abilities and record that, like so: Lightning Quick. When it may apply to an action taken by your Adventurer, offer that up to the GM and let them decide if so.
When Adjectives apply to actions, they give acting character Advantage. If you end up with more Advantage than the opposing force when all is said and done, you'll get more dice to roll as representing said Advantage. Adjectives are each normally worth 1 Advantage, but the exception is: Incredible Adjectives.
Incredible Adjectives end in one or more exclamation points. Lightning Quick is not incredible. Lightning Quick! is incredible. The exclamation points at the end each make it worth one more Advantage when applied in the rules. So Lightning Quick!! is worth 3 Advantage, one for the Adjective and two more for the two exclamation points.
One of the substance rules for traits. A clause is a rule of the game in a specific format. Abilities have one or more clauses, which is how they function within the rules of HAT. Each clause can worded like so: Do <X>, and earn <Y>; or: Earn <Y>, if <X>. X is some condition that must be met, and Y is the mechanical result that you earn. The condition of a clause may be entirely fictional or not, but the result of a clause is always mechanical. To put it simply, clauses always link the fiction of the game to the rules of an Ability. Lets explore the clause used in the Ability: Smash. Smash says: “The player may add the Adjective: Brutal and one level to attack battle actions for the cost of 1 HP.” The condition here is “pay 1 HP” and the result: may add the Adjective: Brutal and one level to attack battle action“. Its as simple as that.
One of the types of substance for traits. While Abilties never have modifiers, Aspects sometimes do, and Attributes always have them. Additional scores count as positive modifiers as well. A modifier is simply an adjust made to the total of a roll. When more than one modifier applies, you sum them to create one modifier from them, as so: A roll that was STR + Stunt is: D20 + STR modifier + Stunt modifier for the total. You then use that total to determine Outcome.
One of the types of substance of traits. When a trait has the Usurp ability, it means that within the limits given, the player can Usurp the normal rules and do that the trait specifies. If the trait does not specify what can be done, that means its something in the vein of the trait created by the player of that character and the GM. For instance, the Elf Aspect trait has this Usurp: ”In addition, they may Usurp the rules for the cost of 2 HP when the GM allows them to perform a stunning feat of physical prowess and earn a level result effect as the GM picks“ That's fancy talk for the ability of the elf to do things outside the normal scope of the rules, if the player pays 2HP and the GM allows. What can this allow: stunning feats of physical prowess. So if your Elf reached a thirty foot wide chasm, perhaps you could pay 2 HP to Usurp and leap it in a daring feat of prowess.
While the Usurp may trigger other game mechanics, and often does, it never has any inside it or rolls. That means the fiction and events of the Usurp are just between the player and the GM. Whatever actions taken in the fiction by the player's adventurer don't trigger the game rules. Above, when jumping the chasm, you wouldn't consult the rules of the game as GM to determine the outcome. Instead you decide that as you envision it with the player's input.
This is one of the three main currencies of play, the others being AC and XP. HP are Hunger Points, and signify the drive and ambition of an adventurer. You can say that the presence of HP makes them an adventurer. There is no direct correlation to the amount of ambition the adventurer has and the amount of HP they possess. Instead, think of it as how far they are from losing all ambition and suffering a Collapse.
A Collapse happens when the adventurer runs out of HP. At this point the player can retire their adventurer and make a new one as the GM allows, if that is what they want for their character. You could picture this as a moment of crisis where the adventurer questions their drive to go on. Regardless of any of that, any Contest the adventurer is currently in is forfeit, combat or otherwise and consequences are figured.
Only Adventurers have any amount of HP (and brutal forces of the wild like monsters and so on). A regular person may have none and in which case they will never have the mettle to become an adventurer, or they may have one to four HP and may have the potential but never realized it.
As a player you will spend your HP in contests to activate Clauses and mechanics. The core one of which lets you buy off the effect of an Attack by paying its Outcome in HP, which is called a Discount.
Of the currencies, HP returns the slowest, meaning at best you get a Draft of +2 HP per round.
Additional are modifier scores (but usually bonuses) in addition to the ones you get from Attributes. All adventurers start with Acumen, Stunt, and Trick as their scores. They may also get more from Abilities and Aspects, examples being Faith, Thievery, and Occult. You can picture these scores as character capability in various areas.
Advantage is a mechanic by which the player (or GM) rolling the dice can get more dice to roll. These dice do not add together, but instead they work as a pool form which you take the highest rolled die as the result. If you rolled three dice and got: 3, 14, and 11, you would keep the 14 as your total. However, there is another option for using Advantage as well: Push.
When you Push, you have your Adventurer leverage some of this advantage for a better outcome instead of better odds at a better outcome. You pay one Advantage AND one HP and trade that for +1 level of Outcome give the roll earns at least 1 Outcome (a roll result of 5+).
Outcome is what you earn from rolling the dice in the game. A roll for Outcome is the roll of a twenty-sided die plus one or more Modifiers, but usually two of them. Outcome means the Adventurer did better at what they were attempting. You earn one Outcome from every full five points you roll. A roll of 17 is 3 Outcome, and a roll of 11 is 2 Outcome. A roll of 4 or less on the die earns no Outcome - EVER. If a roll of 4 or less would have created Outcome (from Modifiers or Push, etc) the player can only earn that Outcome if they pay HP equal to the levels of Outcome they will get. If they do not, or cannot, they earn no Outcome.
When a player earns 10 XP, they get an Advancement. This will let them do one of the following for their characters: