Please post any errors encountered in the handbook here!
Just read through the rules, and I noticed in the pre-made characters that multiples of them have a weapon called "K-12 sunder", classified as a pistol, but I can't see a weapon with that name listed anywhere. Checking through, I realize that K-12 sunder was probably an old name for the M-500 bulkshot, but it might be good to standardize that for clarity.
Heyo! Thanks for the question! Gonna note this too.
Basically think of it as a d6 roll of advantage or disadvantage. If you have advantage, flip again, and if you get a single success you succeed. Disadvantage is the opposite way, and reduces your advantage by 1 per stage of disadvantage.
Say I do +3 advantage with my weapon, but because of something, I also have 1 disadvantage. That reduces to 2 advantage, meaning I flip two coins, and if any of them are heads, I succeed.
On the flip side (lol), if I have 0 advantage on a weapon, but now have 1 disadvantage, I flip 2 coins, and if any of them are failures, I do not succeed.
I need to go back and explain this because I can easily see how this can be confusing without a proper explanation. Thank you for your patience! <3
Don't worry, I really like your work and the GRIM setting has hooked me since I read the preface. If I may make a suggestion about what you just explained, I can think of another way to approach it. You see, as the system is based on D2 rolls, the advantage could be successes that make up for failures and in the case of the disadvantage it would be the opposite, failures that make up for successes, for example if I want to attack a group of Walking Graves and due to the situation I have a disadvantage of 1 and I roll 3 dices, let's imagine that I have 2 successes and 1 failure, then that 1 of disadvantage would turn one of my successes into a failure and in the opposite case if I have an advantage of 1, then that failure I get in the roll would be a success. This way you separate the re-roll mechanic as if it were a new opportunity to try your luck and the case of advantages and disadvantages as something more inherent to the situation of the PJs. I hope my idea helps you to continue with this great project!