In 2001, a stand-alone version of Call of Cthulhu was released by Wizards of the Coast, for the d20 system.

SSS's version of the game, which reached the market in 2003, used the d20 Modern system, and mimicked D & Ds " three core book " model with three hardcover manuals:

Sword & Sorcery Studios also published three paperback supplements for the d20 version of Gamma World:

A version of the setting called " Star Law ", which uses the d20 system rules was published as an alternate campaign setting in the d20 Future book.

In 2003 Wizards released version 3. 5 of Dungeons & Dragons and the d20 system.

He also wrote or co-wrote a few more products for Wizards of the Coast as a freelancer, including the d20 version of Call of Cthulhu.

The rules for the d20 System are defined in the SRD ( currently version 3. 5 ), which may be copied freely or even sold.

The eight-times Origins Award-winning setting has been converted to many other systems over the years and is available in the original Classic Rules, the revised Classic Rules, d20 System, GURPS, as well as a Savage Worlds version called Deadlands: Reloaded.

Despite having a vocal fanbase, the Trinity Universe line was discontinued shortly after the game's publication ; a d20 system version was released in 2004.

Mutants & Masterminds game mechanics are based on the OGL d20 System, designed by Wizards of the Coast, however it is a highly modified version of that basic system.

The SRD specifies the skeleton rules and mechanics — including races, classes, feats, skills, spells, magic items and monsters — compatible with the d20 System version of Dungeons & Dragons editions 3. 0-3. 5 ( the 4th edition represents a substantial revision ) and various other roleplaying games from Wizards of the Coast.

A d20 version, using a similar power creation structure modified for compatibility with the d20 System line, was released two months after the Tri-Stat version.

Many of its concepts were adapted to the d20 version of Big Eyes, Small Mouth.

Silver Age Sentinels d20 System version is also hardcover with a black and white pages.

A version of BESM adapted to the d20 System was published in 2003.

It is one of the few materials produced for the ill-fated d20 version of the game.

The English version of " Engel " does not include the Arcana system at all ; it is based on the d20 System instead.

The German version includes d20 rules in addition to the Arcana system.

Judges Guild returned in 1999, selling revised copies of the City State of the Invincible Overlord, a reintroduction of Pegasus magazine that lasted two issues (# 14 & # 15 ), the Revised Treasury of Archaic Names, and an edited version of Dark Tower, in addition to classic original products ; the company also produced products for the d20 system.

Intended to preserve the feeling of the original game, the d20 conversion of the game rules were supposed to make the game more accessible to the large D & D player base.

* EverQuest Role-Playing Game ( a role-playing game produced in collaboration with White Wolf which uses the d20 system ).

Rather than being a rigidly pre-defined set of rules like d20 System or GURPS, Fudge offers a customizable toolkit for building the users ' own specialized role-playing game system.

The fifth and sixth versions of Gamma World take the game's tendency of mimicking other games to its logical end, adopting the rules systems of other games wholesale: The fifth edition of the game uses the Alternity rules, while the sixth edition uses the d20 Modern rules.

Unlike the d20 System and many other game systems, experience awards are in the form of character points, which have the same value as those used in character creation and can be applied directly to the character's abilities upon receipt.

The Wheel of Time Roleplaying Game was released in 2001 from Wizards of the Coast using the d20 rules developed for the third edition of the Dungeons and Dragons game.

* Lemuria ( role-playing ), a 2004 RPG world designed for the d20 Modern game by Swedes Anders Blixt and Krister Sundelin

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 d20 System is a derivative of the third edition D & D game system.

The MSRD includes material from the d20 Modern roleplaying game, Urban Arcana Campaign Setting, the d20 Menace Manual, and d20 Future ; this can cover a wide variety of genres, but is intended for a modern-day, or in the case of the last of these, a futuristic setting.

Because Dungeons and Dragons is the most popular role playing game in the world, many third party publishers produce products designed to be compatible with that game and its cousin, d20 Modern.

Other criticism is based around the part of the d20 System Trademark License which defines " Open Game Content " to include game mechanics and purports to license it.

An all-Mythos themed CD produced in association with Wizards of the Coast to promote their new d20 edition of the Call of Cthulhu role-playing game.

The game also uses polyhedral dice ( d4, d6, d8, d10, d12, and d20 ) which are referred to as the " Bones ", and a set of red, blue and white poker chips.

However, the OGL was criticized ( primarily by independent role-playing game developers ) for being insufficiently " open ", and for being controlled by the market leader Wizards of the Coast ( see d20 System for more information ).

Though it had a vocal fanbase the whole game line was discontinued due to low sales in 2001 ; an adaptation for the d20 system was released in 2004.

Torg provides a unified mechanics system suitable for any setting ; character attributes and game mechanics use a single sliding scale (' 18 ' can equally mean an hour of time, a truckload of weight, an expert marksman's skill, or $ 4, 000 ) and a unified method of task resolution involving a d20.

* d20 Future ( role-playing game supplement )

These rules formed the basis of the d20 System that is available under the Open Game License for use by other publishers.

The system is a skill based system utilizing 20-sided dice ( it is however not the d20 system published by Wizards of the Coast ), with point based characters.

Traveller < sup > 20 </ sup > ( or T20 ) is the d20 System-version of Traveller, developed by Quicklink Interactive.

A twenty-sided die ( d20 ) is rolled and the result is added to any modifiers for task checks against a standard difficulty target number ( referred to in d20 games as a " Difficulty Class " or DC ).

Drow appear as a playable race in Urban Arcana, which is a d20 Modern setting based on Dungeons & Dragons.

A supplement book about the drow was produced by Green Ronin Publishing called Plot & Poison: A Guidebook to the Drow in 2002 and is based on the d20 System.

Much of the d20 System was released as the System Reference Document ( SRD ) under the Open Game License ( OGL ) as Open Game Content ( OGC ), which allows commercial and non-commercial publishers to release modifications or supplements to the system without paying for the use of the system's associated intellectual property, which is owned by Wizards of the Coast.

To resolve an action in the d20 System, a player rolls a 20-sided die and adds modifiers based on the natural aptitude of the character ( defined by six abilities, Strength, Dexterity, Constitution, Intelligence, Wisdom, and Charisma ) and how skilled the character is in various fields ( such as in combat ), as well as other, situational modifiers.

This system is also consistently used for all action resolution in the d20 System: in prior games in the D & D family, the rules for different actions varied considerably in which dice were used and even whether high numbers or low numbers were preferable.

The d20 System is not presented as a universal system in any of its publications or free distributions, unlike games like GURPS.

This is known as the d20 System Trademark License.

Unlike the OGL, the d20 System Trademark License ( D20STL ) is revocable and is controlled by Wizards of the Coast.

The same round of changes to the license also limited the size at which the text " Requires the use of the Dungeons & Dragons Player's Handbook, Third Edition, published by Wizards of the Coast " ( which is required to appear on the front or back cover of most fantasy d20 System products ) could be printed, and prohibited making part of it larger than the rest.