I began designing my own roleplaying system in the early 90s. After years of playing Dungeons & Dragons (AD&D 1E, D&D Basic/Expert, and AD&D 2E), I was tired of the class concept. I wanted the freedom to build a character from scratch, to decide what abilities I wanted, and determine the path he would follow as he advanced. I wasn’t interested in spending money on more rulebooks to learn a different system, however. So, I started designing my own.

The group I played with all through high school had finally broken up, however. Everyone went their separate ways after graduation, so I had no one to bounce ideas of off or playtest with. Work on the roleplaying system slowed as other activities absorbed my time.

Then WotC released the third edition of Dungeons & Dragons. The rules had taken a huge leap closer to the ideal I had been seeking. I started a handful of campaigns with new groups over the next couple years, but nothing ever stuck. In between those attempts, I pulled out my old “homebrew” system and started work on it again.

I’ve got the core mechanics worked out: character generation and advancement, conflict resolution, and magic. Now I need to add some flesh. That’s a primary reason why I started this blog. I want to introduce the world to d00M, and motivate myself to finish it in the process.

d00M stands for “d100 Mechanic”. The d00M roleplaying system uses a d100 for its core mechanic, the ability check. There are no other dice rolls. Damage is not determined randomly. Starting attributes are generated with point buy. And there are no classes, just a pool of skills to select from.

I will post a section of the rules from time to time. Feedback is welcome. My plan is to release the entire system as a free PDF when it is complete. Nothing fancy, just pages of text. We’ll see what happens from there. To start things off, here is more on the ability check.

THE ABILITY CHECK
The d00M™ RPS is based upon the results of rolling a 100-sided die (or two 10-sided dice), referred to as d100. Any modifiers the player has based upon his character’s attributes, skills, feats or other sources are added to the results of the d100 roll and matched against a Difficulty Rating (DR) determined either by a formula or an opposing roll. This is referred to as an ability check.

To achieve success against a formulaic DR, the player must get a result equal to or greater than the DR. So, if a character’s action has a DR of 60, the player can roll anything from 60 to 100 to succeed.

To achieve success against a DR determined by an opposing roll, the player must get a result greater than the DR. In this case, if the GM rolled a 64, a roll of 65 to 100 by the player would succeed.