Puzzles

Simple brain rolls resolve situations where a call needs to be made regarding the character's intellectual ability. However, most games involve situations where letting the players solve the puzzle is part of the fun. Reducing the identity of the murderer in a whodunnit to a single die roll--or even a series of die rolls--would be anticlimactic. In these situations--which we call puzzles--the goal is to let the players do most of the mental work while using die rolls to resolve the parts of the process that players can't see, do, or know because they're experiencing the game world indirectly and don't personally know all the things that their characters know. Complex traps, criminal investigations, and actionable research and analysis (discovering a monster's weaknesses, documented evidence of wrongdoing, or the antidote to a pathogen, for example) are common examples of puzzles in RPGs.

Creating a Puzzle

Assemble Your Clues

In order to set up a puzzle in your game, you have to start with the solution and work backwards to figure out what information the characters need to arrive at the solution and how they might be able to obtain it. Start by dividing this information into the following categories:

• Obvious Clues: This includes information about the puzzle that the players get "for free" without any die rolls (Dr. Cadaver was shot dead in his home), information about the world that characters are expected to know based on genre convention, core setting information, or details established in previous sessions (Dr. Cadaver is the recently-elected President of the Gentleman Explorers' Society of Hoboken), and general knowledge that players can reasonably be expected to bring to the table (gunshot wounds involve a bullet, powder residue, and other qualities that can reveal information to an expert with the right skills). These clues are either provided in scene description or available for the asking.
• Subtle Clues: Subtle clues are things that the characters can easily sense but are unlikely to recognize as significant. For example, the fact that Dr. Cadaver's fireplace has recently been used. If a player asks for the relevant information or does something that reveals it, they get the answer for free (no die roll required). Otherwise, treat recognizing the significance of the clue as a roll-based clue (on a successful roll a player notices that the fireplace has recently been used, which strikes them as odd since it's July).
• Roll-Based Clues: These are clues that the players have no way of knowing about until you tell them, usually in response to a successful roll. These are usually things that the character senses, but can also include facts that the character might know about the world that a player doesn't know or remember. Examples include a button on the floor that might be from the killer's jacket, the butler's nervous fidgeting when questioned, and details about the recent Explorers' Society election.
• Conditional Clues: These are clues that will only be revealed if the characters take a specific course of action. Sometimes simply taking the action will reveal the clue (if the players dig through the ashes in the fireplace, they'll find bits of burned-up paper with distinctive qualities). In other cases, a roll--or a series of rolls--is necessary (obtaining clues from the blood spatter will require successful forensics roll). Since conditional clues require players to take a particular course of action, it's usually a good idea to come up with some clues that can encourage that action, especially if the action isn't standard operating procedure for the kind of puzzle the players are solving. For example, if the groundskeeper has vital information, you'll need to find a way to let the players know that the groundskeeper exists and perhaps provide hints that he may have valuable information--maybe he found the body, or a witness mentions that they couldn't hear what happened in the study over the sounds of the lawnmower outside.

Determine Clue Costs

Puzzle-solving rolls take a slightly different form than standard rolls, so instead of a Challenge Die value, clues have a cost. Conveniently, though, the rating you would assign to a a "find this particular clue" roll is about right for the cost. Obvious clues and conditional clues that don't require a roll have a cost of zero: the player gets them automatically when they encounter a particular piece of the puzzle or take the conditional action. For subtle clues, the cost is based on the likelihood of the player recognizing the clue as significant (but drops to zero if a player asks). Conditional clues that require rolls often use some other resolution system (witness interrogation, for example, uses the Savior-Faire rules). If this is the case, use the standard rules. Otherwise, assign clue costs normally and use a puzzle-solving roll for the conditional action. As you're setting your clue costs, you'll need to adjust for two specific types of clues:

• Vital Clues: Are clues that the players are very unlikely to solve the puzzle without. Such clues should usually be obvious, but if that doesn't make sense they should be handed out during the first appropriate inquiry turn even if no player rolls high enough to cover the cost (instead, give the clue to the player who rolled closest). The GM should not tell the player which clues are or are not vital.
• Revelatory Clues: These are clues that, if discovered, will almost certainly provide an instant solution to the puzzle. Triple the cost for revelatory clues.

Inquiry Turns

An inquiry is a course of action that characters take to find information that will help them solve a puzzle. For some puzzles, the number of potential inquiries is limited. For example, if the players are trying to figure out how to open a puzzle lock, there are two main inquiry paths: studying the visible portions of the mechanism, and--for characters likely to have relevant knowledge (an engineering background or historical expertise of the culture that built the lock, for example)---trying to recall information that could provide a clue (possibly to a new line of inquiry). A murder investigation, on the other hand, has a large number of potential lines of inquiry: players can search the murder scene for clues, analyze evidence in the lab, question witnesses, investigate the victim's dealings and relationships, study bug activity, and do all the other things that characters do in your favorite murder-of-the-week show. In a well-plotted mystery, most lines of inquiry will reveal new lines of inquiry that the characters can explore (reviewing Dr. Cadaver's journal turns up an account of a recent dispute with a colleague who the detectives can further investigate, spy on, or question).
Since it would be boring to simply let the players continue to roll for each line of inquiry until they find all the clues, we use inquiry turns to create a situation where characters who keep doing the same thing over and over see diminishing returns. This encourages players to explore the puzzle from multiple angles and attempt novel lines of inquiry. During the first round of a particular line of inquiry, each player rolls against 0 Challenge Dice and finds clues with a cost adding up to their successes (or a close as is possible given the available clues). If one or more characters chooses to roll again for essentially doing the same thing, the Challenge Dice for the roll increase by 1 per turn already spent on the line of inquiry and the characters' successes are pooled together. The GM then subtracts a number of successes equal to the number of characters who participated in the roll and hands out clues based on the the result as they see fit.
If the characters switch to a different way of gathering information (for example, they stop investigating the scene of the crime and start questioning witnesses), a fresh line of inquiry begins at inquiry turn 1. However, the turn count for previous lines of inquiries remain in place if the characters return to them. If the characters spend 3 inquiry turns investigating the scene, then go question witnesses, then return to look for more clues, they resume the "investigate the scene" inquiry on turn 4.

Narrowing the Inquiry

Often, characters will learn something that prompts them to resume a previous line of inquiry with more focus: consulting a particular book for information instead of just doing a general search of the library, searching the crime scene for a specific type of evidence that they might not have realized was significant before, or asking a witness about a specific topic or event that they didn't know about during the first investigation. In many cases, narrowing the focus of a line of inquiry eliminates the need for a roll--the information being sought essentially becomes a subtle clue that players can obtain for the asking. If a roll is still necessary, the inquiry turn remains the same, but the players get to ignore the Challenge Dice on the first roll of the more focused search. The Challenge Dice increase normally during said round--so that on subsequent rounds they remain at 1 less than the current inquiry round--they just don't count for that single round.

Fresh Eyes

If a character who has not previously participated in a line of inquiry joins in, they make a separate roll on their first round against the current Challenge Dice and find a clue based on their successes. The new character's successes are not reduced by the number of characters searching, but the new character is counted when determining the group successes.

Insight

At any point during an investigation, a player may spend 1 point of Luck to gain an insight. This allows the player to choose between the following options:

• Ask a Question: The player may ask the GM a question about the investigation, which the GM must answer truthfully. The player can't ask for the solution to the puzzle.
• Get A Hint: The GM must give the player a useful hint to help solve the puzzle: a connection they're missing, an avenue of investigation that they haven't considered, etc. If the players seem to be stalled on solving the puzzle and it makes narrative sense, this can be a good time for the GM to reveal revelatory clues that the PCs have missed, or at least give them a hint that might prompt them to return to the line of inquiry that can reveal a revelatory clue.

Racing The Clock

When the time it takes to solve a puzzle matters, start a countdown clock (as described in the Trackers section) to keep track of time spent and let the players  divide their successes between uncovering information and reducing the time spent on each roll.