The basic mechanic
Whenever you roll an attribute (e.g. Agiility, Strength etc) or a Skill (e.g. fighting, notice), you roll the die indicated on your sheet and a d6, taking the highest result. The d6 is your Wild Die, and you get it because you are what's called a Wild Card. All PCs are Wild Cards, as are some important NPCs. Non-wild cards are called Extras, and only get to roll the die indicated on their sheet.
If a maximum is rolled on a die, then it 'explodes' and you reroll and add the total. This can happen multiple times and occasionally leads to very high totals.
When you roll your dice you will be aiming for the Target Number (TN). In the most basic case this will be 4. However, this can be modified by circumstances as decided by the GM to be made easier or harder.
For example, shooting a standing target in good light with no cover at short range has a TN of 4. Shooting a prone target (-2) in medium cover (-2) at long range (-4) gives a TN of 12.
Also, the TN when fighting starts at your opponents Parry.
With opposed rolls, the attacker always rolls first and spends any bennies they want to improve their result. The defender rolls second. In a tie, the struggle usually continues in some way.
If you get a roll of 4 higher than the TN, you get a raise. For each additional 4 higher you get an additional raise. For example, with a TN of 4, if you roll 13 you get two raises.
Raises sometimes have an effect on the outcome of a successful roll. For example, in combat, a raise on a fighting or shooting roll gives you additional damage.
If you do not have a skill you are asked to roll, sometimes you will be able to make an unskilled roll. To do this you roll d4-2. You still get the Wild Die, so overall you roll d4-2 and d6-2, taking the highest result.
There will be occasions where unskilled rolls are not allowed, e.g. lock picking, knowledge(medicine)
If you are trained in a skill, you can assist the character carrying it out. Each success and raise adds +1 to their total up to a maximum of +4, apart from Strength rolls, which have no maximum.
If you roll snake eyes, that is double 1, you have a critical fail. This means something really bad has happened, as determined by the GM. There is a setting rule in this campaign that bennies cannot be spent to reroll critical fails.
Every player starts each game session with three “Bennies”, although some Edges and Hindrances modify this.
You receive additional bennies during play for great roleplaying, overcoming major obstacles, playing to hindrances etc.
You can use Bennies to reroll any Trait test and Skill roll. When you spend a benny to reroll, you reroll all the dice, and take the higher number from the reroll or the original. The only exception is if you roll a critical fail, which you cannot benny, and have to take as your roll, even if you previously rolled higher.
You can also spend bennies to try to avoid wounds that you take (called making a Soak roll), or to automatically remove a Shaken status on your character.
Additionally, there is a setting rule called Heroic Determination, where you can spend a benny to take any Combat Edge for a single round