D&D Gamma World provides you with dozens of monsters to use in your games, both in the original boxed set and in Famine in Far-Go. However, it lacks rules on how to build your own custom monsters – rules that are located throughout several books in Gamma World’s sibling game, Dungeons and Dragons.

This document is designed to help you, a D&D Gamma World Game Master, create your own monsters from scratch and use them in your games. Options are also provided for random monster creation when appropriate, and some of the formulas used in monster creation are shown in gray boxes.

Let’s get started!

Download “Mutant Building Made Easy” now!

I’ve just updated the consolidated Ancient junk table and the Gamma World GM screen to remove a duplicate entry.

Also, the GM screen is taller (cut off the top 2 inches when printing on 11 x 17 cardstock) and has more information, plus a graphic.

Download the Ancient junk table

Download the GM screen

Feedback is welcome!


Here’s the Game Master’s Screen I put together for the new version of Gamma World. It’s designed to fold up and fit inside the D&D Gamma World box.

Instructions for creating the screen:

1. Download the file.

2. Print it out on 11 x 17 cardstock, double sided, color print.

3. Cut off the top 2.5 inches.

4. Fold it into thirds and prop it up in front of you. Ta da! GM screen.

This screen includes the following:

  • Index to important rules in the rulesbook (including FiFG rules!)
  • Ancient junk table (including FiFG junk plus Dungeon 185 rules)
  • Skill check DCs
  • Encounter difficulty table and XP budgets by number of players, for planning encounters
  • Skill challenge chart with XPs per level (as per FiFG)
  • End of encounter checklist
  • Starting gear table (player-side, including gear from FiFG)
  • Weapons and armor charts (player-side)
  • List of conditions (player-side)
Download It Now!