Shadows of Cthulhu
Shadows of Cthulhu is an alternative Call of Cthulhu RPG for players used to the d20 system used by Dungeons & Dragons, Pathfinder, and so many other role-playing games.
Shadows of Cthulhu uses the True20 system created by Green Ronin. I'm certain the publisher and game designer, Reality Deviant Publications, fitted Lovecraftian horror to the True20 system to draw in gamers who use the most conventional set of role-playing rules in the world.
True20 Core Rulebook
To
play Shadows of Cthulhu, you'll need to have a copy of the True20
core rulebook. The game system is going to look pretty familiar to most
people, but it's got enough differences from D&D 3.0 and 3.5 that you'll
want to have your own version of the rules system.
How True20 Works
People used to d20 roleplaying are going to be able to play Shadows of Cthulhu without a lot of time spent learning a new game. True20 is a modified d20 set of rules whose major departure is the character professions or archetypes: warrior, adept, and expert.
The warrior is what all D&D fighter classes would fit under. The adept involves any kind of psionics or magics, whether it's wizardry, sorcery, or divine magic. The expert is for characters whose main advantage is skill, so characters like rogues, bards, rangers, and nobles fit under this class.
Shadows of Cthulhu Suggestion
Anyone who's ever played the Call of Cthulhu RPG might be asking themselves whether those classes are going to work for a campaign based on the Cthulhu Mythos. In particular, you might think the adept class is fine for sword-and-sorcery games, but ill-fit for play in a Lovecraftian setting. In Cthulhu games, magic tends to be mysterious and dangerous to wield. Most magic-users are crazed cultists whose mind has been warped by their knowledge of the mythos.
For this reason, it's recommended GMs disallow the adept character when beginning your campaign. You might let a character grow into the adept category. The Call of Cthulhu role-playing game allows players to learn magic rather quickly by increasing their Cthulhu Mythos score, though virtually any magical knowledge is bought at the price of a reduction in your sanity score. When your sanity gets too low (or if you lose too much sanity at once), you go temporarily or permanently insane.
Reading the original tales from H.P. Lovecraft and friends, that's the way magic and sanity should be handled in a good Cthulhu campaign. This can be done with a few tweaks of the "Shadows of Cthulhu" setting and the publishers are happy to offer their suggestions.
Shadows of Cthulhu Sourcebook
Shadows of Cthulhu contains chapters for character creation, life in the 1920s, tips for running games in a Shadows of Cthulhu world, and special rules for insanity. You'll also get a chapter which tells you how to convert standard Call of Cthulhu stats to the skills, abilities, and characteristics of the True20 system. Other chapters include a bestiary of monsters, descriptions of the Old Ones and their entire preternatural pantheon, and a separate section on the cultists and human NPCs you'll be trying to stop from summoning such horrors.
The Shadows of Cthulhu book also contains a map of the village of Dunwich, where awful things are happening. The 10th and final chapter contains more suggestions for running the campaign with additional information on the insanity system. All in all, you should have what you need to run a d20 variant of Call of Cthulhu, or at least a True20 version close enough your players shouldn't mind the change of pace.
About Reality Deviant Publications - Gunmetal Games
Reality Deviant Publications was founded in August of 2005 because the owner of the company wanted to enter a supplement they wrote in a public contest. Since then, Reality Deviant Publications has released 75+ gaming products. In 2009, the owners had a contest to rename the company in order to avoid confusion with the competing Reality Blurs company. These days, you'll find Reality Deviant Publications under the name "Gunmetal Games".
Games and game supplements offered by GunMetal Games these days include Reign of Discordia, Interface Zero, the I-Zine, Heroic Toolkits, The Survivor's Guide Series, A Touch of Evil Series, The Beyond Modern Series, and Scarrport: City of Secrets. Here's a short description of the full game settings offered by the old Reality Deviant Publications include games like Interface Zero, Reign of Discordia, and Colonial Gothic.
- Interface Zero - Cyberpunk setting using the True20 System.
- Reign of Discordia - Science fiction and starfaring game by Darrin Drader using either True20 or Traveller.
- Colonial Gothic - American Revolutionary War setting with vampires and other monster.
Shadows of Cthulhu should have a niche among the versions of Call of Cthulhu on the market. As great as the original d100 version of Call of Cthulhu is (and it's great), I've met many D&D gamers who want no part of a whole new game mechanic. So for many of the same reasons Mutants & Masterminds found widespread approval with the gaming public--its d20 game mechanic--True20 roleplaying and Call of Cthulhu should find a crowd of players willing to give it a try. True20 and its open-ended character class system is meant to be adaptable to any type of players, so there's no reason True20 shouldn't be able to power a horror game based on H.P. Lovecraft's Cthulhu mythos.