The most common dice you’ll use in Gods & Monsters are the d20 and the d6. You’ll use the d20 on its own. This is a die with twenty sides, ranging from 1 to 20.
You’ll usually use more than one d6 and add them together. If you see the term “3d6”, this means to roll three six-sided dice. Unless the rules say otherwise, you’ll add those three dice together. If you roll a 3, a 6, and a 5, this is a 14.
You will also use four-sided dice (d4), eight-sided dice (d8), ten-sided dice (d10), and twelve-sided dice (d12), usually for things like survival points and weapon damage. You might see “2d4” for rolling two four-sided dice and adding them together, or “1d8” for rolling one eight-sided die. For all dice except d4, you read the top number (just as you do on a d6). The d4 doesn’t have a top number, so you read the bottom number, which is usually printed along the sides.
Adventure Guides will sometimes use a d100. It is unlikely that you have a hundred-sided die. You’ll generate a number from 1 to 100 by rolling two ten-sided dice of different colors or sizes. One of the dice will be the tens die, and the other will be the ones die. If you roll a 1 and a 9, this is 19. If you roll a 4 and a 2, this is 42. If you roll two zeroes, this is 100. Most of the time when you are rolling d100, you are checking a percentage. So if something happens 65% of the time and you roll less than or equal to 65, this something has happened. If you roll 66 or greater, this something has not happened.
Go to godsmonsters.com/Game/Dice/ for a dice-reading demonstration.