• What is the CoCGMS?

    What is the CoCGMS?

    The CoCGMS or Call of Cthulhu Game Management System is an app developed on the FileMaker platform.  Thousands of businesses and developers create amazing systems using FileMaker.

    The CoCGMS is a game management system intended to give Call of Cthulhu gamers a complete set of tools needed to create both characters and scenarios as well as provide a wide range of other features like catalog tracking, combat utilities, table creation, dice rolling abilities, and much more.

    Scroll through the showcase here to see some of the system features.



  • Character Creation

    Character Creation

    The CoCGMS features a great character generation system allowing you to create templates from which you can quickly roll out dozens of randomized NPCs, Monsters or Player character records; each one having a unique blend of stats, skills weapons and equipment you set the ranges for.  The system is highly customizable to give you the ability make nearly any option just what you want.

    Each character record can have any number of character images assigned to it and built in dice rolling tools let you use a character record interactively to speed up the pace of running a CoC game.

  • Scenario Creation

    Scenario Creation

    Many gaming applications focus only on character creation and dice rolling utilities.  But, there's more to a game than just characters and rolling dice.  There has to be something for the characters to actually do!

    The CoCGMS has a powerful scenario development side which will help you create the other half of a role playing game.  You can store any number of scenarios in the system and have all of your content in one place, ready to reference instantly.

    Write your scenarios just like you would a book with chapters breaks to separate things into chunks.

  • Scenario Tools

    Scenario Tools

    Scenarios can be packed with a huge amount of data such as the actual narrative content of each part, images, character links, dialog, combat groups for rapid fighting resolution and even sound boards.

    Load your scenarios up with sound bytes to play for your players to spice up the flavor of a game or even pre-record dialog spoken by an NPC they might encounter at some point to make sure you get the tone just right.

  • Scenario Parts

    Scenario Parts

    In the CoCGMS, scenarios are built by creating parts of the whole.  This allows the keeper to compartmentalize his or her content into easily found and referenced chunks of information.  Major parts of the scenario are broken down into chapters and within those chapters are parts like events, group references, historical information, etc.  These part types are customizable by the keeper to be just what he or she needs them to be.

    Order your parts in the logical order you need and move sections easily if necessary.  Attach images, notes, dialog, printable items and more to each part.

  • Catalogs Galore

    Catalogs Galore

    Use the CoCGMS to store customized catalogs of anything you may need to reference or assign to characters.  Each package in the system can be loaded with catalogs of melee items, range items, spells, skills, print templates and much more.  Organize things by era or any other logic you see fit to use.

    Nearly all entries can store an image helping you flesh out the feel of all items.  Attach catalogs to packages, scenarios and/or directly to characters themselves to provide a base selection of available items.

  • Table Concatenation

    Table Concatenation

    Give your brain a break!  Let the CoCGMS create unique things for your game but concatenating up to 7 tables of things into truly interesting outcomes.  Leverage features that let you build just the right thing generator.  Build interesting names out of syllable strings, generate new insanities, describe people your PCs meet on the street at the click of a button, and more.

    It's amazing what you can come up with by letting the system string together a few random possibilities.

  • The Players Window

    The Players Window

    The CoCGMS is both a behind the scenes development tool set AND an interactive gaming utility designed to be used as you game.  One of the best interactive features is the Players Window which displays things for the players to see as you game like images, dice roll results, table selections, GM jotted text and more.

    Using a third party utility like "Actual Multiple Monitors" you can mirror the contents of the Players Window to a dedicated monitor facing your players.  Turn off the mirroring of content when you need to or clear the Players Window at will to keep the players from seeing too much!

  • Print It!

    Print It!

    Print characters the way you need to.  Print full character sheets for the players, 3x5 quick reference cards for NPCs, tack sheets of just names and occupations to give to players as help sheets for knowing each other or NPCs, tent cards to stand up in front of players, and more.

    Print out your scenarios to have a paper copy handy or print Print Items attached to scenario parts such as journal entries, found telegrams, doctor's prescription orders, etc.  Install a free PDF print driver like PrimoPDF and send everything to PDFs to keep on your computer outside of the system.

  • Many More Features

    Many More Features

    The system is packed with many more features than covered here in the showcase.  Download a copy and give it a try!  The CoCGMS is completely free.  No nag-ware, no ads, no in-app purchases, no donation requests, no charges at all.  Just free to have fun with.

  • Multiplatform


    The CoCGMS can be installed on Windows, Mac and iOS (iPad) platforms.  For Windows and Mac versions of the app, just download the correct zip file to your system, unzip and run.  No installation needed.  Just run CoCGMSv2.exe (Win) or the CoCGMSv2 app (Mac) and you're off and running.  Make additional folders to hold multiple copies of the app if you'd like.

    For iPads, download FileMaker Go from the app store (free) and then download the raw database file from MPConnection.com and transfer to FileMaker Go on your iPad using iTunes and run the database from within the FM Go app.

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Suggested Utilities

We all have our favorite apps.  I have mine like everyone else and here are a few that work well in conjunction with the CoCGMS...

Actual Multiple Monitors

AMM is a great Windows utility by www.actualtools.com and gives you enhanced controls over the monitors attached to your system.  If you're like me you have at least two and possibility three monitors attached to your workstation.  AMM lets you do things like define grids on your monitors you can use to drop app windows into and have them automatically resized.  It's best feature for use with the CoCGMS is window mirroring.  AMM can be used to mirror the contents of an app window or even an app child window to a dedicated monitor.  Using this feature you can mirror the CoCGMS's Player Window to a dedicated monitor which is facing the players and show them output generated by the system like images, dice rolls, table selections, GM posted text and more. 


Honeyview for Windows by www.bandisoft.com/honeyview is a highly customizable image viewer.  Along side of outputing images in the CoCGMS to the Players Window, you can also opt to output image to an external viewer.  Honeyview can be customized to remove all toolbars and screen elements to give a clean display to players.


SimpleDiagrams from www.simplediagrams.com is a versitile and easy to use diagramming app that can do anything from folksy flow charts to basic landscape designs and everything in between.  It lets you create your own object libraries from JPG, PNG and SVG files and add them to your diagram with ease.  You can scale your obects up or down and layer them as needed.  Makes a handy mapping tool for basic encounters or simple topography maps with some creativity.

 FileMaker Pro

I can't forget giving a spiel about FileMaker Pro (www.filemaker.com).  As you know, the CoCGMSv2 is a FileMaker database.  FileMaker is an award winning database system which has been used over the years by thousands of companies and users all over the globe.  Unlike SQL, FileMaker is schema, data and presentation all in one package.  Design your interface and store your data in the same engine.  Happy as a workgroup app or scalable for hundreds of concurrent users, FileMaker can be a client/server application or a stand alone developer package.  FM16 was just released on 5/9/2017.

Multi-Monitor Viewer

This freeware utility allows you to view the display of any monitor attached to your system in a stand-alone app window.  This is very useful with the CoCGMS if you are displaying the Players Windows on it's own monitor that faces your players but want to be able to see it too.  Launch this app and select the monitor to view and it's displayed in an app window.  You can then mouse over to the Players Window monitor and still see your mouse pointer allowing you to interact with that display and still see where your pointer is.


ZoomIt is a classic SysInternals utility for drawing on your screen.  It's free and has been around for years.  It still works great under Windows 10.  You can use it in combination with Multiple-Monitor Viewer (above) if you are using the Players Window and draw on the display the players can see.  Face the Players Window monitor to the players and launch Multiple-Monitor Viewer so you can see what they see.  Then, use ZoomIt to draw on that display while viewing it in the app window showing that monitor.

Duet Display

DuetDislay (www.duetdisplay.com) is an incredible utility that lets you link your iPad to a PC or Mac as a 2nd display via a usb cable (the best responsiveness level is always hard wired).  This can be used as the Players Window for the CoCGMS and gives you a very portable player facing display for showing game content to the players.  Upgrade to DuetDisplay Pro to gain some high end drawing functionality to your main system.  I like to use it with my Windows 10 system and SimpleDiagrams.  I link my iPad Pro up to my laptop as a new display then place SimpleDiagrams on it.  The Wacom level Apple Pencil sensitivity works perfected for drawing in SimpleDiagrams.  Obviously there are some nice drawing apps natively for iOS but having the ability to use high resolution drawing tablet features on a full graphics app on a Windows (or Mac) machine is hard to beat.


FileBrowser (https://www.stratospherix.com/products/filebrowser) is an iOS app ($) that lets you browse network resources and transfer files back and forth between an iPad or iPhone and a Windows or Mac PC.  This is useful in transferring the CoCGMSv2.fmp12 database file from your workstation to your tablet without needing iTunes and a physical USB connection between devices.  Once in the FileBrowser file store, you can send a copy of the CoCGMSv2.fmp12 file to the FileMaker Go app.  You can also share a file within FileMaker Go back to FielBrowser then use FileBrowser to upload it back to a workstation.  When iOS 11 comes out and more flexible inter-app file sharing is available, transferring directly to & from FileMaker Go should be greatly enhanced.


FileMaker Go can natively access content saved to iCloud.  You can place a copy of the CoCGMSv2.fmp12 database file onn your iCloud drive and pull it down inside of FileMaker Go.  You can then upload your edited CoCGMS back to iCloud from where it will be accessible to your Windows or Mac workstation.