RPG Encyclopedia: O

0-9ABCDEFGHIJ-KLMNOP-QRSTUVWX-ZIndex
Obsidian: The Age of Judgement
1st ed by Micah Skaritka, Dav Harnish, Frank Nolan (1999) Apophis
2nd ed (2001)
A mystic post-daemonic-apocalypse science-fantasy RPG, set in the year 2299, after the manifestation of Hell upon the Earth Plane in 2029. It is set within the "Zone", a massive monolithic structure housing the remains of Humanity. They are threatened by "Daemons" from outside which feed on sin, and sympathetic "Kultist" within. Characters have the option to play heavenly characters imbued by the Divinity, daemonic characters who serve the daemon hordes, or neutral characters that serve only themselves or the megacorporations within the Zone. It uses a skill-based dice-pool system: total (attribute + skill) d6's vs. difficulty.
octaNe
1st ed by Jared A. Sorensen (2002) Memento Mori Theatricks
A post-apocalyptic RPG set amidst "trash-culture" America. It uses a dramatic system based around Plot Points, though it also uses die rolls. There is one supplement, "Against the Reich", which adapts the game for two-fisted pulp serials fighting Hitler, including 30 new character Roles.
Odysseus
1st ed by Marshall Rose (1980) FGU
A fantasy RPG set in an indeterminate period of ancient Greece. Includes brief rules for warships and naval rule.
Oem Prime
1st ed (1997) Omnimarcus
A fantasy RPG system. The system uses the special icon-marked 12-sided dice ("Success Dice", "Battle Dice", and "Body Dice") that it uses.
The Official Superhero Adventure Game
1st ed by Brian Phillips (1981) self-published
A generic superhero RPG, focusing mainly on combat.
Of Gods and Men
1st ed by Jeffrey Konkol (1997) Non-Sequitor Productions
An epic fantasy RPG. The system is level-based with some skill templates and only human characters. During character creation, the player draws three divinity cards with the "divine power" their character has (Skill Gain, Flight, etc.). Character creation uses random-roll attributes (take 5 highest of 7d10 for each of six attributes) and point-bought skills.
Og: The Role-Playing Game
1st ed by Aldo Ghiozzi (1995) Wingnut Games
2nd ed (2000)
Unearthed ed by Robin D. Laws (2007)
A humorous beer-and-pretzels mini-RPG about cavemen vs dinosaurs. Players choose 1 of 5 types of cavemen: strong caveman, smart caveman, fast caveman, hitting caveman, or healthy caveman. The twist is that players are limited to a 17 word vocabulary at all times: you, me, rock, water, fire, tree, hair, bang, sleep, smelly, small, cave, food, thing, big, sun, and go.
OGL Ancients
1st ed by Adrian Bott (2004) Mongoose Publishing
A game covering the broad genre of ancient history and legend, focusing on the Egyptians and Greeks before the rise of the Roman Empire. It uses a variant of the D20 System from third edition D&D and D20 Modern. It is, however, a complete core rulebook released using Wizards of the Coast's Open Gaming License (OGL).
OGL Cybernet - Cyberpunk Roleplaying
1st ed by August Hahn (2003) Mongoose Publishing
A game covering the broad genre of cyberpunk and netrunning, using a variant of the D20 System from third edition D&D and D20 Modern. It is, however, a complete core rulebook released using Wizards of the Coast's Open Gaming License (OGL).
OGL Horror
1st ed by Gareth Hanrahan (2003) Mongoose Publishing
A game covering the broad genre of horror, using a variant of the D20 System of third edition D&D and D20 Modern. It is, however, a complete core rulebook released using Wizards of the Coast's Open Gaming License (OGL).
OGL Steampunk
1st ed by Alejandro Melchor (2004) Mongoose Publishing
A game covering the broad genre of steam-age science fiction, using a variant of the D20 System of third edition D&D and D20 Modern. It is, however, a complete core rulebook released using Wizards of the Coast's Open Gaming License (OGL).
OGL Wild West
1st ed by Gareth Hanrahan (2004) Mongoose Publishing
A game covering the broad genre of wild west action, using a variant of the D20 System of third edition D&D and D20 Modern. It is, however, a complete core rulebook released using Wizards of the Coast's Open Gaming License (OGL).
Okahoshin
1st ed (unknown) unknown
A Japanese-language fantasy RPG, set in mythic China (Oka). Roughly translated: "Immortals of the Middle Kingdom". The PC's are immortals who fight various monsters and demons. Character creation is random-roll attributes and class-based special abilities.
Oko Yrrhedesa
1st ed by Andrzej Sapkowski (1995) Wydawnictwo MAG
A Polish-language fantasy RPG, written by a best-selling fantasy writer. The title translates as "Eye of Yrrhedes". The rules were originally a magazine article, then later published as a book (in 1995). The system is simple and aimed at beginning players.
Omnifray
1st ed by Matt West (2008) Omnifray
A fantasy genre RPG set in an original quasi-medieval fantasy world called the Enshrouded Lands. Outwardly the world is populated only by ordinary humans and animals - but there are many magical secrets. Resolution uses a universal table, that gives percentile chances when comparing opposing ability scores. Other aspects of the game use a full range of polyhedral dice. Character abilities are split between ordinary traits and feats that require energy points of a particular type such as physical energy, concentration energy, or fate points. Character creation is limited point-based, using character generation points for your attributes and traits, and versatility points for feats.
Omnigon
1st ed by Dennis Craig, Scott Groves, Alan P. Widtmann, Glenn Zaroski (1989) Omnigon Games Inc.
A sci-fi RPG system. It uses a simple class-based system with six classes: warrior, rogue, infiltrator, scout, psionicist, and alpha knight (semi-psionic warrior).
Once Upon a Time in the West
1st ed by Beck, Spencer (1978) Tabletop Games
A western-genre skirmish combat game which came in 3 booklets, which was officially developed into an RPG with the fourth booklet ("Return of OUATITW").
One Can Have Her
1st ed by Jonas Ferry (2007) self-published
A game inspired by film noir, designed for play in a single evening for a GM and two or more players. Each character is guilty of a crime, and they are competing to get what they want done before their time is up. It uses a resolution system based on playing cards, where hands of cards are played off against each other one at a time. Character creation begins picking one of 10 character types (including Politician, War veteran, Journalist, Gangster) and one of 10 attributes (including Paranoid, Depressed, Idealistic, Hardboiled). The player then decides upon their character's life goal (what they hope to achieve before they die). The GM then chooses who each character's enemy is, and introduces the femme fatale, the one woman each player wants, but only one can have.
The One Ring: Adventures over the Edge of the Wild
1st ed by Francesco Nepitello, Marco Maggi, Amado Angulo, Dominic McDowall-Thomas (2011) Cubicle 7 Entertainment Limited
A fantasy roleplaying game set in the world of Middle Earth by J.R.R. Tolkien five years after the events narrated in The Hobbit in the area of Wilderland (the region visited by Bilbo in his journey to the Lonely Mountain). Resolution is by 1d12 (the Feat Die) with 1d6 for each level of skill. Success is measured by the number of sixes rolled. Characters have 3 attributes (Body, Heart and Wits) - each with six associated skills for a total of 18 skills. There are also Valor and Wisdom social stats along with Hope points (used for extra dice for rolls along with other effects) and Corruption (used for the influence of evil). The set comes with an 192 page Adventurer's Book and 144 page Loremaster's Book.
On Her Majesty's Arcane Service
1st ed by clash bowley (2009) Flying Mice LLC Precis Intermedia Games
A historical fantasy RPG, set in the reign of Queen Elizabeth I in 16th century England. The players characters are part of Her Majesty's Arcane Service, a secret force headed by John Dee to protect England from mystical attack. It uses a dice pool system, the StarPool dice mechanic, also used in later editions of the Starcluster RPG. The game includes rules for creating a branch of the service, including capital, base, type, and various resources. Character creation is via a lifepath system, with various options including Half-angel, Changeling, Hunter, Esotericist, Magus, Templar, Savant, Warlock, and Minstrel. There are magic rules similar to those in Blood Games II.
On Mighty Thews
1st ed by Simon Carryer (2011) Simon Carryer Games
A sword and sorcery fantasy game based on Robert E. Howard's Conan stories. It uses a simple scene-based system using step-die resolution. Character creation starts by assigning a d4, d8, and d12 to three base attributes - Warrior, Sorcerer, and Explorer. Players then choose two freeform attributes assigned a d6 and a d10 as well as a single-word d20 trait. After character creation, players and GM collectively create the setting by drawing a map and marking it with each character's d20 trait and adding features related to these. Play proceeds by scenes that the GM creates and the players add details to. Resolution is by taking the highest result of rolling all dice that apply, compared to a difficulty (default 4) or opposed roll. Foregoing a d20 roll can earn the player a reroll token.
On Stage!
1st ed by Luca Giuliano (1995) DaS Productions
An Italian-language acting game. The original game assumes that the players take on the role of the main characters in various Shakespeare plays. It uses cards to determine events. The basic rules include a scenario based on Hamlet. Supplements and other works have extended it to other genres. Official supplements include "Sogno di una notte di mezza estate" (Shakespeare's A Midsummer Night's Dream); "Biancaneve e i tre porcellini" ("Snow White and the Three Little Pigs") a mixing of traditional fairy tales); "Fagioli dollari e polvere da sparo" ("Beans, dollars and gunpowder") about Sergio Leone's Western movies; and "On Stage! Epico" about King Arthur's knights.
Open Core Role Playing System
1st ed by Christopher Helton, Jamie Borg, Ewen Cluney, Richard Gazley, Tim Huntley, Jonathan M. Thompson (2004) Battlefield Press
An open-license system based on the D20 System used by 3rd edition D&D. It eliminates class mechanics, replacing it with open point-based character generation. Action resolution uses 3d6 + Attribute + Skill vs. target number.
Opening the Dark
1st ed by Malcolm Sheppard (2007) Mob United Media
A modern dark fantasy/horror RPG, closely based on White Wolf's World of Darkness games, with the core mechanics released under an open gaming license. The player characters may be investigators of dark mysteries, or monsters at the heart of the secrets. The basic game includes guidelines for set powers, freeform magic and spirits. It uses a dice pool system, rolling d10s equal to attribute plus skill, where every result from 7 to 9 is one success, and every result of 10 is two successes. Total successes are compared to difficulty.
OpenQuest: D100 Gaming Made Easy
1st ed by Newt Newport (2009) D101 Games
"Con-Quest" ed (2010)
A generic fantasy role-playing game, based on Mongoose Games' RuneQuest SRD with ideas from previous editions of Chaosium's RuneQuest and Stormbringer 5th. Magic is divided into Battle Magic, Divine Magic, and Sorcery. The basic game includes a sample setting ("The Empire of Gatan") and a sample adventure ("The Road Less Travelled"). The content is entirely open gaming content released under Wizards of the Coast's Open Gaming License.
Open Versatile Anime RPG
1st ed by Clay Gardner (2005) Wise Turtle Publishing
A universal RPG which aims at broadly emulating Japanese anime genres. It uses a rules-lite dice pool system, the "Richochet" system. Character creation is by simply picking a number of freeform traits and flaws, rated numerically. For action resolution, you roll a number of d6s based on which freeform traits apply to an action. You add together doubles or take the highest die and compare to a GM-set difficulty number.
Opera RPG 'Beholders Lost in Alternative Realities'
1st ed by Leonardo Andrade, Rogério Godoy (2004) Comic Store Comercial Ltda
A Portuguese-language universal system, billed as "The Ultimate Guide to RPG Worlds Creation". There is also an English-language shareware version and upcoming print version. Action resolution is roll under stat on 2d6, or stat + 2d6 for contests. Character creation is open point-bought. The basic game includes world-building system, martial arts, psychic powers, magic, and superpowers rules.
Operation: Fallen Reich
1st ed by Mikael Reidal (2009) Fallen Publishing
A historical occult mystery game - subtitled "Can Evil Be Stopped In Time For Tea?" - where the player characters are ordinary but colorful British citizens who come to fight the strange forces behind the Nazi party on the eve of World War II. These are supernatural creatures called the Fallen, who have plagued mankind for millenia. The game uses a simple system with detailed skills but no attributes. Resolution is by 1d20 + skill vs. difficulty. Character creation in the full game is by a separate physical board game (the Life Board). The player draws four cards from a custom deck (Start Cards), each with a profession and a personality trait. They select the profession from one card and take the personality traits from the others. The profession defines a starting spot on the Life Board, and the player then plays 16 rounds on the board, rolling a die to move to different squares each time and collecting a Destiny Card.
Oráculo
1st ed by Joaquim Micó (1994) Joc Internacional
A Spanish-language RPG about mythic-age Greece. It uses a simple rule system with roughly 20 pre-defined profession templates. You roll from 1d4 to 2d6 depending on your profession and the task, plus percentile special abilities. Combat is handled in one roll, add attacker bonus and subtracting defender bonus to find damage. It has several supplements.
Orbit
1st ed by Jeff Diamond (1998) 6-0 Games
A light-hearted spacefaring sci-fi RPG, including dungeon-like labyrinth worlds. It uses a simple skill-based system, where character creation is based on 1 of 8 professions. The resolution is percentile based. Experience is based on creatures killed and money acquired.
Ork!
1st ed by Todd Miller, Chris Pramas (2000) Green Ronin Press
A satirical play-the-monsters RPG, where you play a murderous, back-stabbing psychotic interested in naked, merciless power. It uses a simple system rolling a number of dice (1-5) based on skill and die type (d4-d20) based on attribute vs a number of d6's based on difficulty (2d6-5d6).
Orkworld
1st ed by John Wick (2000) Wicked Press
A fantasy genre RPG based around a hunter-gatherer race called "Orks", set on the world of Ghurtha. The culture and background of the Orks is heavily detailed. The system is a dice-pool system, taking the highest of skill+attribute d6 -- except multiples of the same number add +1 to the that number. e.g. A roll of 1,1,2,3,5,5,5,6 would keep 5's for result of 5+1+1=7. Also, a special rule for ties is that you compare all the dice until the tie is resolved. Character creation is done by the players collectively creating a household with a single pool of points. Advancement is by managed fana (fame) points handled by the group's tala (bard).
Orlando Furioso - Il gioco di ruolo dei Paladini di Re Carlo
1st ed by Andrea Angiolino, Gianluca Meluzzi (1993) City Council of Rome
2nd ed (2002) Rose and Poison
An Italian-language fantasy RPG, based on the Italian poem of Ludovico Ariosto. It uses a simple rule system intended for for new players. The first edition was published by the City Council of Rome and freely distributed to teachers and librarians for educational purposes. The expanded second edition from Rose and Poison includes a section on mythological monsters. Both editions are illustrated with classical engravings by Gustav Doré (from circa 1800).
Orpheus
1st ed by Bryan Armor, John Chambers, Genevieve Cogman, Richard Dansky, B. D. Flory, Harry Heckel IV, Ellen Kiley, James Kiley, Matthew McFarland, Dean Shomshak, C. A. Suleiman (2003) White Wolf
A modern horror game, where the PCs are ghosts (or Laments) who are working for a company called the Orpheus Group. The company has ghost employees who do various jobs ranging from occult investigations, to spying, to assassination. It uses a variant of the Storyteller system.
Orx: Nasty, Brutish, and Short
1st ed by Ravenscrye Grey Daegmorgan (2003) Wild Hunt Studio
A darkly comedic fantasy game about playing orcs, creatures hated by the gods and doomed to die. It uses a narration-based dice pool system. Each orc has three attributes: Nasty (social), Brute (physical), and Grok (mental). They also have a Fate stat, which starts at 1 and rises as they choose to tempt fate. Players can roll extra dice on any roll, but this raises their Fate stat, which is used to check if they die when defeated. Character creation is by assigning a d6, d8, and d10 to the three stats, as well as picking three player-defined descriptors such as "Fast-Talking" or "Distance Spitting Champion". Play is in scenes, where the GM has a limited amount of opposition dice available per scene.
Other Suns
1st ed by Niall Shapero (1983) FGU
2nd ed (1989) shareware
A spacefaring sci-fi RPG, set in an interstellar empire (the "L'Doran Hegemony") with 11 species of anthropomorphic animals. Centuries ago, humans fought a devastating war with the Hegemony and eventually lost, reducing Earth to ash. Now, scattered human worlds (former colonies) have joined the Hegemony in re-exploration and settling of the galaxy. It uses a percentile skill-based system. Character creation has random-roll attributes. cf. Ermine's Other Suns Online page.
Outfan. A Space Operetta
1st ed by C. Piniol, J.P. Romeu, R. Mercadal (2002) Planeta-DeAgostini
A Spanish-language humorous starfaring RPG, which parodies the science fiction from Jules Verne to "The Matrix". It includes an original background with nine races and four star systems. The system is percentile-based. Character creation uses a set of 20 generic professions. cf. the official web page.
Outime
1st ed by Marc W.D. Tyrrell (1983) Valhalla Simulation Games
A time-travel RPG for adventures on alternate Earths. The system is similar to original Traveller, covering psionics.
Over the Edge
1st ed by Jonathan Tweet (1992) Atlas Games
2nd ed (1997)
A modern-day "psycho-surreal" RPG, set on a fictional island in the Mediterranean where paranoid conspiracies, alternate realities, and bizarre strangeness collide. It uses a minimalist system where each character is described by 3 narratively-defined traits and 1 fault. The number of dice you sum for a task depends on which (if any) of your traits it falls under.
Oz Dark & Terrible
1st ed by S. Alexander Gentry (2010) Emerald City Expeditions, LLC Studio 2 Publishing
A fantasy RPG set in a dark variant on L. Frank Baum's Land of Oz just prior to the first book. For example, the Tin Woodsman is a retired member of the Wizard's oppressive secret police, while the Cowardly Lion is an exile who refused to eat the hearts of humans to gain lycanthropic powers. It uses a d10 dice pool system, where players roll a number of d10s equal to the sum of traits, and add their skill to the total. One die in the pool is always the Luck Die, which is open-ended. Character creation is point-based, including buying magic via ratings from 1 to 5 in various spheres (such as Fire, Mind, or Life).

John H. Kim <jhkim@darkshire.net>
Last modified: Thu Apr 14 22:02:47 2016