Being a tabletop game, Orchestra has a method of conflict resolution that relies on random chance so that storytelling can be structured by some modicum of balance for each player. Orchestra was actually originally built to be a vessel for its dice system (OrchestraS), though it's become more complex since, so the system is somewhat unique and complex. As a player's aid, there is a dice-roller at Anydice.com, written by Catlike Coding (both the site and the actual rolling math).
Orchestra would be pretty boring about rules for how the action takes place. Or, rather, pointless. The exact way specializations work was mentioned when they were first brought up for character creation, but it's nice to have a refresher and a little explanation.
All actions in Orchestra are handled roughly the same- there's 3 categories, 8 attributes, and roughly 4 skills for each attribute available for players to specialize in, and when an event happens, the appropriate specializations are used to roll for the outcome. Of course, it's not always necessary to roll. For the sake of drama or realism, it may be better just to say that the researcher knows what an object in a laboratory does, even if he doesn't come across them often. Of course, if he wanted to use it, he may have to make a Science check to figure out its operation.
The ''basic roll'' in Orchestra consists two six sided dice. Both of these dice will be rolled (or simulated), and then the result will be added. Specializations are handled differently. Specializations allow additional dice to be rolled, one for each applicable specialization, for up to three additional dice. The top two dice (from specializations or the basic roll) are chosen as ''primary dice'', and the remaining dice have their results halved (rounding down, zero is allowed) and added to the result as ''secondary dice''. The ''final result'' is the sum of primary and secondary dice, as well as any modifiers for double specializations in specific skills. When in a challenge, the highest number wins, whether the challenge is against a static target, or an opposing character. Skills are not necessarily used against the same skill. The skill ''Ranged Weapons'' is not rolled against ''Ranged Weapons'' in a normal opposed test during combat, though it may be for an opposed test at a marksmanship competition. In any case, a roll is made and then checked against a number, with the goal being to have the highest number.
Some actions require skill specialization. These tend to be the exception rather than the rule- almost anyone can pick up a gun and pull the trigger, or look around and spot something out of the ordinary, but it takes someone with a fair amount of training to perform advanced mathematics. Some actions cannot be undertaken (with any chance of success) without the desired skill. Some skills do not use basic dice, meaning that only dice for specializations are rolled, and then only if the skill specialization for that skill is present (attribute or color category specialization alone does not suffice).
Actions can also have a ''Stamina Penalty''. If the action fails, [Red/Bulk/Endurance] is rolled against a certain target number to avoid losing stamina. Psi actions always have a stamana check, regardless of success. Stamina's starting amount is equal to health. When stamina is depleted, a character has to drop out of the action for the rest of a scene (he's still there, but can't make any rolls. Stamina is regained at a rate of two points per scene.
Bill shoots at a target. He rolls his Red, Agility, and Ranged Combat specializations (he has all three) as well as the basic roll. His five dice come up 1, 5, 4, 6, and 4. He keeps the 5 and 6 as his primary dice, and adds 2 and 2 for the fours. He winds up with a final result of 15, which is pretty spectacular. Jim has no specialties pertaining to guns, but attempts the same shot. His dice come up as a 4 and a 3. He adds these two dice as his primary dice, and gets a final result of 7. This is probably enough to hit the target, but Bill has a much better hit. Later, Bill tries to shoot the hook on a crane to cause it to drop what it is lifting. He rolls a mediocre (for him) final result of 9, the target is 13 for the shot, and he fails. Ranged Combat has a Stamina Penalty of 1, so he marks off a tick of Stamina.