The following is a list of resolution systems used by roleplaying games. I’m sure someone has already done this, but that’s not the point. I remember things best when I create them. By creating this list, I hope to increase my knowledge of our wonderful, geeky hobby and become a better game designer. (It helps to know what’s out there.) Also, I hope this list will help people understand rpg mechanics more easily and help game designers decide on what system would work best for their game.  I welcome comments, advice, additions, etc. That said, please limit these to the forum page dedicated to this list. Otherwise, this page will go feral and become impossible to read. Thanks!

Dice

Can be divided into system dependent and character dependent.

Dice/System Dependent: Number and type of dice rolled set by system.

Roll Higher: Roll one or more dice, add or subtract modifiers, and get higher than a target number to succeed on task.

• D&D 4E: Roll 1d20 +/- ability modifier +/- misc. modifier over target number (AC, difficulty, etc.).
• D20: Roll 1d20 +/- ability modifier +/- misc. modifier over target number (AC, difficulty, etc.).
• Dying Earth: Roll 1d6 +/- difficulty; 3 or higher to succeed. Spend ‘ability pool’ points to reroll.
• SIEGE: Roll 1d20 + attribute over 18 (or 12 if within a skill bundle).

Roll Lower: Roll one or more dice, add or subtract modifiers, and get lower than a target number to succeed on task.

• HarnMaster: Roll 1d100 under skill for success. (Note: d100 is usually done by two d10s but it counts as a single die.)
• In Nomine: Roll 2d6; add results, lower than target number to succeed; roll 1d6 as check digit for degree of success or failure, higher means larger degree.
• PARANOIA XP: Roll 1d20 under stat rating. Spend ‘Perversity’ points to increase/decrease roll result.
• D10x (Cyborg Commando): Roll 2d10 and multiply the numbers rolled, roll under a target number for success.

Die-Stat Roll Higher: Add a die roll result to a character attribute and get higher than a target number to succeed on task.

• SLA Industries: Roll 2d10 + stat higher than 11.
• HoL: Roll 2d6 + stat + skill +/- difficulty; 15 or higher to succeed.
• Unisystem (AFMBE): Roll 1d10 + stat + skill +/- difficulty, 9 or higher to succeed.

Pool Roll Lower: Roll a number of dice set by the system and get lower than a target number for success on task.

• Wushu Open: Roll 1d6 and add d6′s for each narrative detail added; roll a 2 or lower.

Dice/Character Dependent: Number and/or type of dice rolled set by character attributes.

Pool Roll Higher: Roll a number of dice equal to a character attribute, count how many are higher than a target number.

• Burning Wheel: Roll d6′s equal to stat’s exponents; higher than 3 is a success; count successes to succeed on task.
• D6: Roll several d6s equal to stat rating; add results; over difficulty number for success.
• Dogs in the Vineyard: Roll several dice; add two highest dice; higher number wins. Can ‘Raise’ (as in poker) and add 1-3 dice results to total until someone cannot/does not match the raise with dice results of their own.
• Hot War: Roll dice, compare against other dice, highest roll wins; number of winning dice indicate level of success.
• Sorcerer: Roll several dice; compare highest die to threshold or opponent’s highest die; highest number wins; if tied, go to next highest.
• Ubiquity (Hollow Earth): Roll dice, count number of evens,
• World of Darkness: Roll d10s equal to stat rating; count how many are above 7.

Pool Matching: Roll anumber of dice equal to a character attribute, count matching dice.

• One Roll System (ORE – Godlike): Roll several d10; count how many match (i.e. 2, 2, 2 ….).

Step Roll Higher: Roll type of dice set by character attribute, roll higher than a target number to succeed on task.

• Savage Worlds: Roll type of die according to stat (d4, d6, etc.) higher than target number.
• Cortex System (Serenity): Roll two dice, type set by stat and skill; add result; higher than difficulty number for success.

Diceless

Can be divided into comparison, randomizer, and narration

Diceless/ Comparison

Numbers: Compare character attributes to determine success.

• Amber: Compare stats; higher stat wins.

Diceless / Randomizer

Cards: Use playing, Tarot, or similar cards to determine success.

• Everway: Draw from a tarot-like deck; GM interprets results based on card name and up/down status as it is turned face up.

Coins: Flip a number of coins to determine success.

• Prince Valiant: Flip coins equal to stat, +/- difficulty; number of ‘heads’ equal to or higher than target number to succeed.

Diceless / Narration

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