Universal

Universalis is a role-playing game (RPG) from Ramshead Publishing that stresses interactive storytelling. The game uses a unique system, based on "coins" that are used to make additions to the game, which allows the entire group to participate in the creation of the setting and events in play without a traditional gamemaster. The rules also provide a means of negotiating their own alteration, allowing for unlimited customization for play. The system is meant to support any possible genre.

Unisystem is a generic role-playing game system produced by Eden Studios, Inc. It is used in All Flesh Must Be Eaten, the Buffyverse role-playing games, CJ Carella's WitchCraft, Conspiracy X (2nd Ed.), and several other games. Games designed using Unisystem have been nominated for, and won, Origins Awards.

TWERPS (The World's Easiest Role-Playing System) is a minimalist role-playing game (RPG) originally created by Reindeer Games (whose sole product was the TWERPS line) and distributed by Gamescience. Presented as a parody of the complicated RPG systems which were prevalent at the time while still being a playable game in its own right, its simple structure and humorous nature gave it unexpected popularity. TWERPS was originally created, written and illustrated (in a distinctive cartoony style) by "Jeff & 'Manda Dee", Jeff Dee being a noted game illustrator and co-writer of Villains and Vigilantes.

True20 is an award winning Role-playing game system designed by Steve Kenson and published by Green Ronin Publishing. The system was first published as a part of the Blue Rose role-playing game before being published as a stand alone universal generic role-playing game, True20 Adventure Roleplaying.

Big Eyes, Small Mouth is a tabletop role-playing game that was designed to simulate the action of anime and manga. It is frequently referred to by the acronym BESM. The title alludes to the common anime drawing style of characters with huge, expressive eyes and comparatively small mouths.

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.

The Storytelling System, formerly Storyteller System, is a role-playing game system created by White Wolf, Inc. in 1991 that premiered in Vampire: The Masquerade, a part of the World of Darkness series.

Savage Worlds is a generic role-playing game and miniatures wargame written by Shane Lacy Hensley and published by Pinnacle Entertainment Group. The game emphasizes speed of play and reduced preparation over realism or detail. The game received the 2003 Origin Gamers' Choice Award for best role-playing game.

The SAGA System is a role-playing game system that uses "fate cards" to determine the effects of actions. The cards have numbers, suits, positive and negative states, and role-playing cues that guide the gamemaster in telling the story and administering the game. The system has been used in TSR, Inc.'s Dragonlance: Fifth Age game and the Marvel Super Heroes Adventure Game, later published by TSR. Sue Cook was the brand manager for both of those game systems, and helped design the SAGA game rules.

Roleplayer is a role-playing game published by Roleplayer Enterprises in 1983.

Risus: The Anything RPG is a rules-light generic role-playing game (RPG) written, designed and illustrated by S. John Ross of Cumberland Games and Diversions. Risus is available free on the web. It was first published online in 1993. Earlier versions of the game were titled GUCS: The Generic Universal Comedy System (a parody of GURPS) and were distributed privately beginning in 1989.

The Open Game License (OGL) is a public copyright license that may be used by tabletop role-playing game developers to grant permission to modify, copy, and redistribute some of the content designed for their games, notably game mechanics. However, they must share-alike copies and derivative works.

Masterbook is a generic role-playing game that was created by West End Games as a follow-up to the multi-genre role-playing game Torg and the science fiction game Shatterzone, which used a modified version of the Torg system. As of January 2011, it is published by Precis Intermedia Gaming.

The Hero System (or HERO System) is a generic role-playing game system that developed from the superhero RPG Champions. It is used as the underlying mechanics of other Hero Games role-playing games such as Dark Champions, Fantasy Hero, Star Hero, and Pulp Hero. It is characterized by point-based character creation and the rigor with which it measures character abilities. It uses only six-sided dice.

The Generic Universal RolePlaying System, or GURPS, is a tabletop role-playing game system designed to allow for play in any game setting. It was created by Steve Jackson Games and first published in 1986 at a time when most such systems were story- or genre-specific.

Fuzion is a generic role-playing game system created by the collaboration of R. Talsorian Games and Hero Games. The rights to Fuzion are jointly held by Mike Pondsmith of R. Talsorian Games, along with Steve Peterson and Ray Greer of Hero Games.:150 Fuzion is a combination of the Interlock System, (used in games like Mekton and Cyberpunk 2020), and the HERO system (used in Champions, Justice, Inc., Star Hero, etc.). Fuzion is an adaptable system which can be played in any genre and setting imaginable.

Fudge is a generic role-playing game system for use in freeform role-playing games. The name "FUDGE" was once an acronym for Freeform Universal Donated (later, Do-it-yourself) Gaming Engine and, though the acronym has since been dropped, that phrase remains a good summation of the game's design goals. Fudge has been nominated for an Origins Award for Best Role-Playing Game System for the Deryni Role-Playing Game.

Fate is a generic role-playing game system based on the FUDGE gaming system. It has no fixed setting, traits, or genre and is customizable. It is designed to offer minimal obstruction to role-playing by assuming players want to make fewer dice rolls.

The End All Be All game system, commonly known as EABA and pronounced "ee-buh", is a role-playing game system designed to adapt to any imaginary gaming environment. It was created by Greg Porter in 2003. The game cites the Hero System, GURPS, and Call of Cthulhu as influences in its development.

The d20 System is a role-playing game system published in 2000 by Wizards of the Coast originally developed for the third edition of Dungeons & Dragons. The system is named after the iconic 20-sided dice which are central to the core mechanics of many actions in the game.

The D6 System is a role-playing game system published by West End Games (WEG) and licensees. While the system is primarily intended for pen-and-paper role-playing games, variations of the system have also been used in live action role-playing games and miniature battle games. The system is named after the 6-sided die, which is used in every roll required by the system.

The CORPS game system, or Complete Omniversal Role Playing System, is a generic role-playing game system. It was created by Greg Porter in 1990.

Basic Role-Playing (BRP) is a role-playing game system which originated in the fantasy-oriented RuneQuest role-playing game rules. A percentile skill-based system, BRP was used as the basis for most of the games published by Chaosium, including Stormbringer, Worlds of Wonder, Call of Cthulhu, Superworld, Ringworld, Elfquest, Hawkmoon, Elric!, and Nephilim. However, Pendragon (acquired in 1998 by Green Knight Publishing, and 2005 by White Wolf), while related, has sufficiently different mechanics that it can be seen as a separate system. The BRP standalone booklet was first released in 1980. Two years later it became part of the Worlds of Wonder boxed set. The first edition boxed set of Call of Cthulhu included the booklet as its character creation rules. Greg Stafford and Lynn Willis are credited as the authors.

Amazing Engine was a series of role-playing game books that was published by TSR, Inc. from 1993 until 1994. Each publication employed the same minimalist generic rules, as described in the Amazing Engine System Guide, but each world book had an entirely different setting or genre. David "Zeb" Cook was credited with the design of the game rules.

Active Exploits is a diceless set of role-playing game rules by Precis Intermedia Gaming. The core rules (which contain no setting) are distributed for free as a pdf file, or for a fee as a printed book. There are a number of published game settings and official game conversions which use these rules.