d20 System
The twenty-sided die, or d20, is practically synonymous with tabletop roleplaying, going all the way back to its use in the original release of Dungeons & Dragons in 1974. But the d20 system we know today didn't actually come about until D&D 3rd edition, after Wizards of the Coast bought the rights to the game from its original publisher TSR. This edition standardized the use of the d20 into a core mechanic, something D&D didn't really have before. While some rules used the d20 in earlier editions, there was no standardized mechanic for resolving everything; rather each situation had its own dice, tables, and procedures, which may or may not have included a d20. The core mechanic of the d20 system, as introduced in 2000 with D&D 3E, involves rolling a 20-sided die, adding any bonuses, penalties, or other modifiers, and comparing it to a target number, sometimes called a Difficulty Class or DC. If the result of the roll is equal to or higher than the DC, the roll is a success. If it's lower, the roll is a failure. This determines the result of the rolling character's attempt. Bonuses come from a character's stats, skills, abilities, and equipment, and additional bonuses or penalties may arise from their specific circumstances and opposition. This mechanic resolves the use of skills, attacking other creatures, knowledge checks to determine what a character knows or remembers, and more. A roll of 20 on the die, or "natural 20," is the best possible result, and depending on the game, it might be a critical hit, an automatic success, or simply the best your character could have possibly done. A roll of 1, or "natural 1," might be an automatic failure, the worst possible outcome, or a devastating fumble. Wizards of the Coast created the d20 system as a "standardized" system for roleplaying games, and placed on an open license so that other games could use it as well, making them broadly compatible. D&D 3E's updated system 3.5, as well as its spiritual successor Pathfinder used this system, as did plenty of other games, including Mutants and Masterminds, Spycraft, 13th Age, Big Eyes Small Mouth, and Conan: The Roleplaying Game. Technically, after Wizards produced D&D 4th Edition in 2008, they were no longer using the d20 system. However, the core mechanic was essentially the same, and most people today use the term "d20 system" not to refer to the specific generic ruleset of D&D 3E and 3.5, but to any roleplaying game that uses the "d20 plus modifiers compared to target number" as its core mechanic. Under that definition, D&D 4th and 5th editions, Pathfinder 2E, Cypher System, Shadowdark, Stars/Worlds/Cities Without Number, Quest, Lancer, Shadow of the Demon Lord, and many, many more use a modified version of the d20 system. To stretch the definition even further, some people might use "d20 system" to describe any RPG that uses a d20 in its core mechanic's resolution, opening the door to "d20 roll-under" systems where players want to roll low on the d20, under their stat or target number to succeed, or games that otherwise roll a d20 but don't add to or modify it, like Mörk Borg and its variants, Perils & Princesses, Cairn, Mausritter, Into the Odd, and many other games.
Popular RPGs using d20 System
Dungeons & Dragons 5e
Dungeons & Dragons 5e is the most popular tabletop role-playing game on the market. With its simplified rules, diverse settings, and player-driven customizability, it’s easy to see why! Perhaps you’ve dreamed of slinging arrows like Legolas, crushing enemies like Conan, or attacking angry chickens like Link—you can make that a reality in D&D 5e! There are three main aspects to a game of D&D: combat, exploration, and roleplay. Different games will feature different balances of these depending on how the people like to play but it’s up to you and your Dungeon Master (DM) to craft a world that you love! Whether it’s the Forgotten Realms, Critical Role’s Wildemount/Exandria, your own steampunk-themed world where wizards ride dinosaurs, or anything in between—your imagination truly is the limit!
Pathfinder 2e
Pathfinder 2nd Edition is a tabletop roleplaying game, or TTRPG, in which players create heroic characters to embark on fantasy adventures. You might play as a noble elven wizard, a roguish halfling scoundrel, or a stout dwarven warrior, just to name a few. Pathfinder is famous for the incredible variety of options players can choose from; there are over three dozen character classes alone, so intrepid players might just as well choose the sword-and-sorcery wielding Magus, the spooky Witch, or the gritty Gunslinger! One player, the Game Master (GM), acts as the rest of the world those heroes explore. The GM presents encounters with memorable characters, mystical places, terrible monsters, and myriad other challenges to overcome. The players decide on a course of action using their characters’ skills, magic spells, or equipment—the only limit on what they can attempt is their imagination! Often, they’ll need to roll dice to find out whether they succeed or fail. But no matter what, the players’ choices result in a unique story of which they are both author and audience. For this reason, TTRPGs are often considered games of collaborative storytelling. Pathfinder Second Edition revamps the rules from the game’s first edition, making character creation, adventuring, and combat more intuitive and easy to learn. It and its predecessor remain as two of the most popular roleplaying games in the world!
Dungeon Crawl Classics
You’re no hero. You’re an adventurer: a reaver, a cutpurse, a heathen-slayer, a tight-lipped warlock guarding long-dead secrets. You seek gold and glory, winning it with sword and spell, caked in the blood and filth of the weak, the dark, the demons, and the vanquished. There are treasures to be won deep underneath, and you shall have them. Return to the glory days of fantasy with the Dungeon Crawl Classics Role-Playing Game. Adventure as 1974 intended, with modern rules grounded in the origins of sword & sorcery. Fast play, cryptic secrets, and a mysterious past await you.
Dungeons & Dragons 3/3.5e
In August 2000, Dungeons and Dragons 3e became the first edition to be published by Wizards of the Coast, who had acquired the previous publisher, TSR, in 1997. This edition saw the introduction of Skills, Feats, the Sorcerer class, and more, in addition to removing the previous editions' restrictions on class and race combinations. Three years later, in July 2003, a revised version of the 3e rules was released that made lots of small changes to the rules, and expanding on the Dungeon Master's Guide and Monster Manual. This version, known as 3.5e, sought to address balancing and gameplay issues from 3e, and made many changes to help improve the game.
Pathfinder 1e
Pathfinder 1st Edition is a tabletop roleplaying game, or TTRPG, in which players create heroic characters to embark on fantasy adventures. You might play as a noble elven wizard, a roguish halfling scoundrel, or a stout dwarven warrior, just to name a few. But Pathfinder is famous for the incredible variety of options players can choose from; there are two dozen character classes alone, so intrepid players might just as well choose the sword-and-sorcery wielding magus, the inspiring skald, or the gritty gunslinger! One player, the Game Master (GM), acts as the rest of the world those heroes explore. The GM presents encounters with memorable characters, mystical places, terrible monsters, and myriad other challenges to overcome. The players decide on a course of action using their characters’ skills, magic spells, or equipment—the only limit on what they can attempt is their imagination! Often, they’ll need to roll dice to find out whether they succeed or fail. But no matter what, the players’ choices result in a unique story of which they are both author and audience. For this reason, TTRPGs are often considered games of collaborative storytelling. Pathfinder’s publisher Paizo has since released a second edition, but the first edition (or 1E) remains one of the most popular roleplaying games in the world!
Lancer
Lancer is set 15,000 years from the present day, where a revolutionary interplanetary state, Union, struggles to win a better world for the whole of humanity. You’ll not see the project complete, but you’ll put your shoulder to the wheel, struggle, and advance. There are many pilots in the galaxy, but only one of you. Your character is a lancer, a mech ace renowned for their skill in their machine. Developed half a millennia prior to the current day of Lancer’s setting, mechanized chassis — mechs — have redefined how war is fought across the Orion Arm. Under your command, your mech is a weapon unparalleled, and with your mech and your comrades by your side, you’ll write your own story.
Starfinder
Gather a crew of expert spacefarers, with a diverse set of origins and skills, get a ship and fly the stars! Starfinder is a tabletop roleplaying game, or TTRPG, of heroic science-fantasy adventure. Players take on the roles of fantasy creatures familiar or alien, and adopt one of over a dozen character classes with various skills and powers, from the battle-hardened Soldier and savvy Mechanic, to the space-wizard Mystic and stellar-powered Solarian! One player, the Game Master (GM) plays as the rest of the vast universe, including the player characters’ allies and opposition, and presents scenarios and obstacles for them to overcome. The players decide on a course of action using their characters’ skills, magic spells, or equipment—the only limit on what they can attempt is their imagination! Often, they’ll need to roll dice to find out whether they succeed or fail. But no matter what, the players’ choices result in a unique story of which they are both author and audience. For this reason, TTRPGs are often considered games of collaborative storytelling.
