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Tri-Stat dX is a generic role-playing game system developed and published by Guardians of Order in 2003. Like other generic role-playing game systems, Tri-stat dX has adaptable rules that can be applied to many genres and settings.

Tri-Stat dX's name comes from the system's three main Stats: Mind, Body, and Soul. "dX" refers to the polyhedral dice used in the game: any of the available die types may be used.

It is based on the original Tri-Stat System first introduced in 1999 with the popular Big Eyes, Small Mouth anime-genre RPG (which used d6 dice), and the superhero-genre RPG Silver Age Sentinels (which used d10 dice), and now includes a number of related systems and games such as Ex Machina, Dreaming Cities, and Tekumel (which uses a variation of the system).

The core rules for the Tri-Stat dX system were also available as a free download on the Guardians of Order website.[1] However, as Guardians of Order is now defunct, the status of support for the game is uncertain. The most recent incarnation of the game system is in the third edition of Big Eyes, Small Mouth.

Making Tri-Stat characters[]

Since all mechanics in Tri-Stat dX use two dice of the same die type (2d6, 2d10, 2d20, etc.), the first choice a GM must decide the game's Power Level, and thus what type of polyhedral dice to use in their game.

Tri-Stat uses one table of Stat Values which range from 1 (Inept) to 40 (Godlike). (The "human norm" is considered 4.) The bigger the die type used in the game, the more powerful the characters generally are, and achieve Stat Values much higher than the human norm. Playing in a "mundane" (real-world) setting, the GM would set the die type to 2d4, and only allow characters to achieve maximum unadjusted die roll totals of 8. A typical "action-adventure" would use a 2d6, allowing more heroic characters and unadjusted rolls up to 12. Games with transhuman characters would use 2d8, and allow rolls up to 16. Superhero games would use 2d10, or 2d12. Godlike characters would use 2d20.

Character Points[]

Characters in Tri-Stat are built with Character Points. To help keep characters "balanced", each player is given the same amount of Character Points. Depending on the setting's Power Level (and die type chosen by the GM), the GM assigns a number of Character Points to each player to spend on Stats and other abilities. In a "Subhuman" mundane world, the characters have 25 - 50 points. In an "Action-Adventure" setting, characters get 50 - 70 points and so on. Godlike characters could have 300+ Character Points.


Characters in Tri-Stat have three main Stats:

  • Body: a measure of the character's physical prowess and health.
  • Mind: a measure of the character's mental capacity and intelligence.
  • Soul: a measure of the character's spirit and willpower.

Typical Stats range in levels from 1 to 20, although the Stats can go higher depending on the Power Level of the game. Levels of Stat are purchased with Power Points. All Stats begin at one and cost two Power Points to increase one level. (Example: Having a Mind Stat of 6 would cost 10 points, two points each for five stat points, and the initial one). An optional rule the GM can impose increases the point cost for Stats at incremental levels, so that high level Stats require more points to be increased to the next level.

Derived Values[]

Derived Values are determined by mathematical formulas based on the values of the character's Stats.

  • Attack Combat Value: (ACV) [(Body + Mind + Soul) / 3] which is the focus of all the character's Stats to determine their bonus to Hit an opponent during combat scenes.
  • Defense Combat Value: (DCV) [(Body + Mind + Soul) / 3 - 2] which is the character's ability to react against incoming attacks.
  • Health Points: [(Body + Soul) × 5] which is the amount of damage a character can withstand before they are knocked unconscious or killed. These are similar to hit points in other games.

Optional Derived Values:

  • Energy Points: [(Mind + Soul) × 5] an optional Stat used for fueling certain superpower Attributes. When a character runs out of Energy Points, they can no longer use that power.
  • Shock Value: [(Health Points) / 5] for more "realistic" combat scenes, when a character suffers their Shock Value in damage, there is a chance they can become stunned.


Any Character Points left over from buying Stat levels are used to buy Attributes for the character. Attributes represent special talents, perks and superpower abilities a character may have. (With them, characters can fly, cast spells, bend iron bars, etc.) Not all campaigns require a character to have superpowers, so a GM can decide which Attributes will be allowed in their game and which ones will not. Because some Attributes (like Special Attacks, Organizational Ties, Gadgets, Henchmen, and Highly Skilled) are similar to GURPS advantages and d20 System Feats, at least some Attributes will be available to characters regardless of the setting.

Tri-Stat has many kinds of Attributes available to choose from. Each Attribute costs a certain amount of Character Points to purchase a Rank Level in that ability. The costs of an Attribute Level depends on what it can do for the character. Certain Attributes can be modified by Power Modifier Values (PMVs) (which can increase, e.g., a power's area of effect, duration, range, or number of targets, also increasing the point cost of the Attribute per Rank).


Defects are the opposite of Attributes, and represent some kind of flaw or weakness in the character. By selecting Defects, a player can regain Character Points to spend elsewhere. There are many Defects available and each returns an amount of Character Points based on the severity of how much they hinder the character. An Attribute can also be assigned a Defect which brings the cost of the power down. For instance, a beam weapon superpower could require a character's special concentration to maintain, giving an advantage to an enemy force. A Personality Defect could be a mental illness the character suffers from, such as paranoia, delusions, or schizophrenia; or could be simply a character flaw, such as being completely obnoxious and difficult for others to deal with. It should perhaps be noted that in real life a mental illness is not a "personality defect"; rather, the categorisation as used in role-playing games refers to parts of the character that make them more difficult to play than a baseline character.


Skills represent special areas of mental knowledge or technique a character may excel in. Like most games that use Skills, Tri-Stat has a comprehensive Skill list of subjects useful to characters. Of course, players and the GM may add Skills of their devising into the game system if needed. Depending on the campaign setting, certain Skills may or may not be available. For instance, in a Medieval fantasy setting, skills for computers would not be available. Each Skill is also tied to one (or more) of the character's three Stats. Mechanics, for example, is tied to both the Body and Mind Stat. Which one, depends on how the GM feels the character is using it.

Skills are organized as either General or Combat Skills, and are purchased by Skill Points that are separate from Character Points. A character's starting amount of Skill Points and maximum Skill Level is determined by the campaign's Power Level. For example, in a "Subhuman" game, characters get 10 Skill Points and can have a maximum Skill Level of 2. In a "Godlike" campaign, characters get 60 Skill Points and can have a maximum Skill Level of 10. Certain Attributes can give characters more or fewer Skill Points as they choose. A character's level in a Skill determines how well they are at performing it. At Skill level 1 they are "well trained", and at 10 they are "heavenly masters" of it.

The Skill Point cost of a Skill depends on the particular Skill and the campaign setting it is being used in. Unlike many other games, skill cost is not based on its real world difficulty to learn. Instead, skill cost is based on its utility in a given setting. More useful skills cost more. Thus, in a mystery setting, investigative skills would be very expensive, while in a medieval martial arts setting those same investigative skills would be cheap to acquire.

Skills are available with Specializations that subdivide a particular area of knowledge into specific Skills a character is adept at. For instance, if picking the Artisan Skill, a character could Specialize in "Woodworking" or "Plumbing" among others. Specializations only cost one Skill Point to acquire no matter the setting. For example, a character could pick Gun Combat in a modern day setting, and pay 8 Skill Points for 1 level of Gun Combat, and pay one Skill Point to Specialize in pistol (Level 2). When using other kinds of firearms their effective Level is 1, but with a pistol it would be Level 2.

Overview of game mechanics[]

All die roll resolutions in Tri-Stat use two polyhedral dice of the same type. Depending on the Power Level of the campaign, these die types will be different. For "mundane" settings, 2d4 is used; for "heroic-action" settings 2d6 is used; for "post-human" settings 2d8 is used; for "superhero" games 2d10 or 2d12 can be used; and for "Godlike" settings, 2d20 is used. The task resolution mechanic is similar to the method used in GURPS, where rolling lower than the target number is a success and rolling over it is a failure.

Task resolutions[]

Whenever a character needs to roll dice to see if they succeeded or failed at doing something, they must make a dice roll which randomly determines success or failure. There are three kinds of checks in Tri-Stat, Stat Checks, Skill Checks and Contested Checks. Stat Checks are made when the GM feels a check of a character's innate ability is required rather than a specific Skill. Skill Checks are made when a particular area of the character's expertise is being challenged. Contested Checks are made against the actions of another character, or non-player character (NPC), that is challenging the character, and is rolled against what that opponent does.

Stat Checks and Skill Checks are often altered by a Difficulty Modifier as determined by the GM. The Difficulty Modifier is added to the target number (usually the player's relevant Stat score) thus making rolling under the target number harder or easier. Modifier ranges depend on the type of die being used in the game. For instance, when using 2d6, Difficulty Modifiers range from +6 "really easy" to -6 "really hard". For 2d20, something really easy would be +20 and really difficult is -20. In all cases, average difficulty is set at zero, or no modification.

When making a Stat Check, a player must roll a total, with two dice, that is less than or equal to the value of the character's Stat. For example, making a check to open a heavy door, a player must roll equal to or less than the numerical level of the character's Body Stat. If the roll was higher, the character has failed at the task.

When making a Skill Check, the player selects the particular Skill being challenged and adds the Skill's numerical level as a bonus to the Stat it is tied to. The player must roll less than or equal to the modified Stat Check to succeed the task. Like a Stat Check, a higher roll is a failure. Often a GM may decide a particular task requires at least one level in a specific Skill, otherwise the character cannot perform the task or must do so as an Unskilled Check, where depending on the general familiarity of the situation, the GM adds in or subtracts Modifiers for the action.

When directly challenged by another character or NPC, a player makes Stat and Skill checks as normal, but the results must be greater than the opposition's results to succeed. GMs may levy Difficulty Modifiers for favorable or unfavorable circumstance as they see fit, if the particular challenger is at an advantage, or disadvantage during the contest.

Combat scenes[]

Time in Tri-Stat is measured in Rounds which represent about 5 seconds of real time. Rounds are linked together in Scenes. A Scene changes when the specific events and places happen to change in the game. For example, a brawl Scene in a bar would change if the fight is moved out to the parking lot. During a Round, a character can take one of several kinds of Actions, such as Move, Attack, or Defend.

Combat can be seen as a bunch of contested actions made against particular adversaries, however the character uses their Attack Combat Value as the number they must roll equal to, or less than, to score successful attacks against the opposition. Their ACV can be modified by Combat Skills, like Gun Combat, and any Specializations with a particular weapon to score a better hit against the target. Characters roll for Initiative (2 dice + ACV), during a Round of combat to see who goes first. The higher roll "Gains Initiative" and allows the character to either take action first, or hold and wait to see what their opponent does.

Defenders of attacks roll their Defense Combat Value to see if they defend against an incoming attack. If they roll less than or equal to their DCV, they successfully defend against the attack whether or not the attacker succeeded his ACV or not. A failed Defense roll means the attack got through and the target takes damage.

Resolving damage[]

Characters can take damage from either suffering an injury or from an attack in combat. Each attack has a Maximum Damage Rating (MDR), which is the total amount of damage points a particular weapon or accident situation can inflict upon the victim. When an attack makes it through a defense, the defender takes damage from the attack. Depending on the Power Level of the campaign, the damage is rolled with 2 dice and consulted on a Damage Percentage Table. The particular roll will indicate that the target took 25%, 50%, 75%, or 100% of the attack's MDR. The attacker's Attack Combat Value is fully added to the resulting percentage of MDR to determine the total amount of damage inflicted upon the target. Damage is then deducted from a character or object's Health Points.

There are also optional damage rules, like a BESM-like approach where attacks always deal 100% damage (although 75% would be closer to the BESM damage increments) or the damage system from Hong Kong Action Theatre!, where the margin of success of both attacker or defender determines whether the attack deals 100% or 50% damage or completely misses.

Critical Hits are inflicted whenever an attack die roll comes up as a 2. The attacker automatically hits the target (who cannot defend against it). The target then suffers double the MDR of the weapon plus the attacker's ACV in damage.

If a character loses all their Health Points, they fall unconscious and are dying. If their Health Points drop to the full negative amount of their Health Points they die. For instance, a character who has 25 Health Points dies when their Health Points reach -25.


Game Masters reward Tri-Stat characters with Advancement Points which the players can use to purchase better levels of Stats, Skills and Attributes.

External links[]