What is Roll and Keep?Edit
Roll and Keep(RnK) refers to the primary dice mechanic used originally in the 7th Sea rule system. Using ten-sided dice(d10s), players roll a number of unkept dice, then keep and add the totals of their kept dice, notated as XkY.
Determining the values of X and Y is simple. For nearly every roll in the game, a player rolls her character's ranks in the selected knack plus a number of kept dice equal to a Trait , or major defining ability. Adding these together results in a roll equal to Knack + Trait Keep Trait, XkY.
Annie, a wild-west gunslinger, wants to take a shot with her revolver. The Gamemaster (GM) tells Annie's player to roll Attack(Pistol) off of Finesse. Annie has 3 ranks in Attack Pistol (3k0) and 2 Finesse (2k2) - resulting in a roll of 5k2.
Target Number - TNEdit
Every roll has a Target Number it must meet or beat to succeed. For most non-combat actions these TNs are determined by the GM based on the difficulty of the action taken. These TNs may also be adjusted by raises - a player may call raises on any roll, taking a -5 penalty on his roll per raise, but achieving much greater success if the TN is still met. Raises may also be required if the action taken is sufficiently difficult or the character is hindered in some way.
Annie has strolled into a new town, making something of an entrance at the local tavern. She's hunting down a local bandit and feels the need to show the townsfolk she means business - being a vigilante fighter type, she decides to show off her marksmanship.
Annie can choose to simply roll an Attack (Pistol) off of Finesse to shoot one of the bottles off the wall. This would have a fairly low TN (5) due to the stationary nature of the target. But Annie wants to do something impressive. Annie's player decides instead to clip a bottle of whiskey with the shot, sending the whiskey tumbling into the hands of the barman for her first drink of the day, and sending the bullet itself into the forehead of the wanted poster of the man she wants to hunt down. This action is much harder. A good rule of thumb(though it is the GM's call) is that every step to an action equates an additional raise - so Annie has to call a raise to clip the bottle in the right way to send it down without just shattering it, then call a raise to ensure the magic bullet is diverted properly into the wanted poster. The target of the shot is still stationary (Typically TN 5) but the raises cause 10 to be subtracted from the roll Annie makes. Rolling a 17, Annie makes the shot and immediately grabs the attention of everyone in the room.
Raises and GamblingEdit
Raises are intended to add a gambling element to the game - essentially a bet that your character is badass enough to pull off incredible things. In that same vein, calling a number of raises and not making the roll can result in disastrous consequences, generally at the GM's discretion.
In the above example, had Annie rolled poorly or called too many raises (attempting to bounce the bullet through four more targets, tying her bootlace while taking the shot, etc.) she could have had her gun misfire, making her the lamest cowboy in town, or a similar fate that hindered her pursuit of justice.
Sometimes a character has to make an action directly in competition with another character - two knights fighting for the same sword, tug-of-war, etc. - in this case, the roll's TN is based on the roll of the opposing character.
Annie has tracked down her bandit, the deadly Catspaw Stevens, and the two have had a long standoff. After rolling Initative (see combat ) and ending up with actions in the same phase, Annie fires at Catspaw, who attempts to Footwork out of the way. This is called an Active Defense - more on that later. For now, know that this results in an opposed roll - the Attack (Pistol) roll Annie is making opposed by the Footwork roll by Catspaw.
Annie rolls Atk (Pistol) + finesse k finesse and Catspaw rolls Footwork + Wits k Wits. Annie's 21 is bested by Catspaw's 24, resulting in Catspaw dodging the shot in time, taking some small bit of cover, etc.
The beauty of this Knack/Trait system is that the mechanics involved can be applied to literally any situation, both in and outside of combat. Social Rolls will be covered more in the Repartee section, but for now know that the RnK system has a strong social backbone to it, arguably a system built for roleplaying in such situations.
Catspaw, actually the character of another player, realizing that Annie means business, attempts to reason with her - explaining the situation as a misunderstanding, and his Wanted status as a framing. This exchange can be handled dramatically between players at the GM's discretion, or Catsby can make an opposed roll - his Charm (wits k wits) vs. Annie's. If he outrolls Annie, he gains her trust. Annie may then decide to aid him in finding the man who framed him, and wacky adventures ensue.