Emily Short is the author of Best Puzzles winners Savoir-Faire and Counterfeit Monkey. She assists in maintaining Inform 7 and is one of the leads on the character-centric IF system Versu. She blogs about interactive storytelling at emshort.wordpress.com and can also be found at meetings of the Oxford and London Interactive Fiction Meetup.

The 2013 Best Individual Puzzle finalists were Threediopolis, Chemistry and Physics, Captain Verdeterre’s Plunder, Faithful Companion, Coloratura and ULTRA BUSINESS TYCOON III.

As I was writing this, I found myself repeating some of the same explanations and concepts in multiple reviews. So, at the risk of making this as much an essay as a review set, I thought I’d start by enumerating some features that I think make a puzzle particularly memorable:

Extent. Does the puzzle provide a significant amount of gameplay, and (equally important) does it stay fresh throughout? There are plenty of puzzles that require many turns to solve without being intellectually satisfying: 15-puzzles, straightforward mazes, towers of Hanoi, and all their equivalents are generally frowned on in IF because the bulk of the player’s effort goes into applying a solution algorithm rather than into discovering what that algorithm should be. On the other hand, puzzles that can be solved in a single move may feel a bit lightweight unless that move requires quite a bit of thinking first.

Explorability. Does the puzzle respond well to failed attempts at a solution? Is it fun to work on even before it’s solved? Is it a good toy as well as a good puzzle? If the player doesn’t immediately understand how the puzzle works, is the implementation responsive enough to help her learn what to do? Suveh Nux is a classic example of the highly explorable puzzle, offering the player lots of entertaining Easter egg rewards for playing with the mechanic while simultaneously helping her more thoroughly understand what the magic syllables do. An entertaining narrator can also improve puzzle explorability: the personality of Grunk in Lost Pig adds charm and humor to the exploration moves required in that game.

Surprise. Does the puzzle require a significant mental leap or a change of perspective to solve? Does it leave the player with the sensation that the world means something different than she expected, like the key puzzle in Photopia? Or does it require assembling diverse bits of information from different sources, or extrapolating further implications of clues learned earlier, like the most famous puzzle in Spider & Web?

Ingenuity. Is the puzzle complex enough that it leaves the player with a sense of mastery afterward, having put together a way through such a difficult terrain? This sounds like it means the same thing as “is the puzzle really hard?”, but with sufficiently good design it’s possible to make a puzzle that leads the player gradually through the learning necessary to implement a fiendishly complicated solution. There are exceptions, but high-ingenuity puzzles most often appear either a) towards the end of a puzzle game with a lot of easier preliminary puzzles, or b) in games that are meant to be replayed a great deal. The Babel Fish puzzle from Hitchhiker’s Guide to the Galaxy is a classic high-ingenuity puzzle, as is the core puzzle of Rematch.

Originality. Does the puzzle present a challenge of a type that hasn’t been seen before, or hasn’t been seen in this genre? Or, alternatively, does it subvert the expectations associated with that puzzle type? Sliding a mat under a door to catch a key poked through from the other side is an ingenious puzzle — it’s just also one that has appeared many times in the IF literature and now qualifies more as a chore than a puzzle, at least for experienced players.

Fairness/accessibility. Is the puzzle consistent on its own terms? Does it avoid making the player read the author’s mind? Does it offer multiple solutions, or allow for partial successes? Does it avoid requiring esoteric knowledge from outside the game that only some players are likely to possess? When the puzzle has been solved, does it retrospectively make sense?

Structural integration. How does this puzzle fit into the overall puzzle design of the game? Is it a first introduction to an important new mechanic or ability, promising a wealth of entertaining gameplay to come? A capstone requiring the player to have learned from a number of earlier puzzles first?

Narrative integration. Is the puzzle thematically relevant to what is going on in the game? Is it a natural fit for its setting? Does solving the puzzle require the player to acquire or demonstrate an understanding of what is going on at the narrative level? How high are the stakes for solving it? Is the player rewarded for the solution with a key event or important new story information? Solving even a simple puzzle can be a powerful moment if it constitutes a critical transition in its story. Make It Good is possibly my gold standard for narrative integration, with puzzles that teach a detailed understanding of the story one is trying to resolve.

I’m by no means proposing this as some sort of scoring system or checklist. It’s exceptionally rare for a puzzle to demonstrate all of those qualities at once, and they’re not equally desirable in all contexts. Indeed, some of these values are typically at odds with one another: it is not easy to make a puzzle that incorporates both explorability and surprise. A puzzle with high narrative stakes and long extent can also be tricky, because tense narrative moments often need to be timed. Puzzles in choice-based games often have an easier time with accessibility than parser games (no guess the verb!), but a harder time achieving surprise (options are enumerated!). Etc.

Rather, nominees in this category showcase the diverse ways that a puzzle can succeed.

Discovering the type of route that works in Threediopolis (Andrew Schultz)

People who have hung around the parser IF community for long will inevitably have run into Graham Nelson’s quote from Craft of Adventure that an adventure game is “a crossword at war with a narrative.” Which sounds cool, but that particular line is quoted more than it deserves. Hardly any IF resembles a crossword. A crossword’s answers are simultaneously available and self-reinforcing. You can do any clue first, and each solved clue contributes new information towards the solution of any other clue.

Having puzzles that reinforce one another is a strategy akin to having multiple solutions: it makes it more likely that each player will succeed, while making it less likely that any given player’s route to success will be exactly the same as any other’s. It’s a significant gain in puzzle accessibility. But it’s very hard to build IF puzzles that way, especially if you’re also trying to make the puzzles gate narrative elements.

Largely ditching any attempt at narrative continuity and a plausible setting, Threediopolis embraces its pure-puzzle nature. (For instance, it states up front that room descriptions are randomly generated and can be switched off if the player finds them distracting.) As a result, Threediopolis is free to be one of the few IF games that truly deserves to be called a crossword: solutions are accretive, all of them are accessible at once, and the more you do, the better you understand the whole system and what the remaining options are likely to be. The challenge is to come up with words made up of the letters N, S, E, W, U, and D, and use them as travel sequences to reach the correct points in a three-dimensional grid. The puzzle hints give you information about word lengths, meanings, and where on the grid you’re going to end up — which means that you can determine some information about the relative number of Es and Ws (say) in the product word.

Before starting on the individual problems, though, you first have to make the leap of understanding what the clues mean. This is, to the best of my knowledge, a unique concept in IF games, born of Schultz recognizing the wordplay potential in the standard compass direction abbreviations.

Getting to that initial understanding may take people in different ways, and is likely to be at least a bit surprising, because so unusual. Some players might work it out just by staring at the list of hints. If they don’t, though, Threediopolis also provides some feedback for exploration. There’s not much else for the player to do except wander the map, and the game gradually spools out additional clues in response: that the grid is limited in each direction, that there’s not much point in trying to hit the edges, that several of the hints point to the same grid node, that “how you get there” must matter as much as the destination itself. The name of the NPC “Ed Dunn” is also a bit of a hint.

Once the player does figure out what kind of input is required, it’s possible to test that idea by solving a single one of the puzzles — which is quite likely to be a one-move solution, or at most (if he strings out the directions over multiple turns) a four or five-move solution. It’s explorable, original, surprising, and the gateway to all the rest of the puzzles in this piece.

Maximizing your profit in Captain Verdeterre’s Plunder (Ryan Veeder)

Captain Verdeterre’s Plunder is a game about rescuing goods from a sinking ship. It belongs to a fairly small group of replayable IF with a score rather than a binary win/lose outcome. The player’s score depends on how much valuable treasure she can rescue from the ship before it slips completely underwater.

To mimic the sinking effect, the game has a dynamic geography: the lowest rooms of the ship naturally fill with water most quickly, and while a room is filling, objects on the floor are endangered first, followed by others. Many IF games involve some change of geography partway through the story (Zork II famously features an earthquake that closes some game areas and opens others), but very few do this kind of progressive, move-by-move map change, which requires constant alterations to room descriptions and door connections. It’s a virtuosic technique, and lends the game a strong sense of urgency.

The result is a complicated optimization puzzle that the player cannot reasonably hope to solve on the first playthrough or two. It’s not immediately obvious which treasures will be worth the most, and your companion Captain Verdeterre is not a reliable source of intelligence. On the contrary, he actively encourages you to pick up things that are essentially worthless, but this is not obvious until the end of your first playthrough. And some treasures take a number of turns to retrieve, while the treasures located lowest in the ship are the first to become unavailable. Playing to optimize, therefore, means running through the game multiple times.

Captain Verdeterre does a lot to make this exploration more rewarding. He’s a highly reactive NPC with some quip to offer about most of your possible actions. The final score itself is also important, since you receive not only a list of the values of each of the objects, but some tidbit about what that object really was, or to whom you ultimately sold it; many of these effectively tell one-liner stories. And the fate of your character gradually improves as your score goes up, as well. Considering that you play as a human sailor in the service of a talking rat, the narrative of this game is not to be taken seriously, and it would be hard to say the puzzle is well integrated with it; fairer, perhaps, to say that the narrative does a good job of frosting the puzzle.

Another fun thing about this process is the way that it builds a fresh challenge out of a lot of simple old-chestnut interactions. There’s a lock and key puzzle, and a couple of puzzles about other ways of opening stubborn objects, and several sorts of searching puzzles (some effective enough that even after I had played the game seven or eight times, I was surprised to read about objects in ClubFloyd’s transcript of the game that I had utterly missed). Without the optimization frame, these would be comparatively ordinary (though even then, they’d still have Veeder’s prose and sense of humor to enliven them). In the context of the optimization puzzle, however, they add an extra dimension. If an object requires a key from another location, that contributes so many turns to the effective “price” of gaining that object — so is it worth it?

Finally, and importantly, this is a puzzle that allows the player to determine her own commitment level. If she wants to play through just a couple of times and call it done, that’s fine — and played at that level, the game is fairly accessible. If, on the other hand, she wants to make a chart of object values and sinking times and opportunity costs, and really commit to the effort, she can come up with a more intricate and ingenious solution.

Veeder’s design notes are a good read, and cover several points that I don’t mention here, as well as providing a little leaderboard for those who feel competitive. I did not beat the highest scores, but I did get my captain enough money to buy his own polar bear, and that’s enough for me.

Three-latch door in Faithful Companion (Matt Weiner)

The three-latch door puzzle is a fake-out, in which the player is initially misled about the very nature of the puzzle in play. It has a fair amount of company in this category. Ryan Veeder’s The Statue Got Me High pretends that it’s going to put you through a logic puzzle about place-cards, and then doesn’t. A number of classic IF works present a fake maze, where it feels as though the player is going to have to run through a standard maze-solution algorithm, but the real solution is something completely different; Photopia‘s recasting of the maze is especially renowned, but there are examples in Curses, Hunter, in Darkness, and many others.

The puzzle-type fake-out can be a dangerous trick, as the IFDB reviews on Veeder’s piece show: players sometimes get as far as recognizing that the puzzle is pretending to be something laborious but don’t play with it long enough to realize there’s a gentler route through, and quit instead. Faithful Companion gets around this: in contrast with many other puzzle fake-outs, it offers a fair, straightforward-to-execute puzzle masquerading as a different but also reasonably tractable puzzle type.

The basic set-up in Faithful Companion is that the player must get all three door latches into the correct position, but the ghost following the player keeps repeating the player’s moves two turns late, and as a result switches the first latch back to its original position before the player has a chance to flip the third.

In play, this feels as though it must be a parity-flipping problem. The latches are carefully implemented and described, and players are trained to focus especially on those aspects of a game that show a lot of authorial attention; and since the ghost doesn’t enter the room containing the latches until two moves after the player does, it may seem as though there’s some latch configuration the player could create during that two-move buffer that would allow him to outflip the ghost. Because the game is responding dynamically (if predictably) to the player’s actions, it’s possible to go on fiddling with the latches for quite a long time: it seems like an explorable puzzle, but is actually a surprise puzzle.

The true solution requires stepping back, viewing the situation through fresh eyes, and considering all of the available tools and options. In a larger game, this might feel unfair, but Faithful Companion is small and focused enough that it’s relatively straightforward to figure out, once the player has renounced the initial incorrect assumptions about unlocking the door in the ghost’s presence.

Getting out of the lab in Chemistry and Physics (Caelyn Sandel and Carolyn VanEseltine)

The main puzzle in Chemistry and Physics involves escaping Dane, a madman who is chasing you with a knife, through a disused laboratory where you used to work. The laboratory contains a number of dangerous objects that you might be able to use to your advantage, but not all of them are equally helpful, and you don’t have unlimited exploration time because Dane is coming after you. The space of the lab is designed so that you can often see him approaching and (usually) escape by going the other way — there are no dead ends to get stuck in — and there is a method of changing where he goes, though it usually has the effect of drawing him towards oneself, which isn’t always desirable.

It is also a timed puzzle: if I took long enough, Dane always caught me eventually even if I tried to be systematic about avoiding the beam of his flashlight approaching me.

The puzzle thus combines a (gentle) Theseus-and-the-Minotaur-style maze play with a time-limited exploration and a find-and-use-object challenge (reminiscent of the timed booby-trap setup in 10 Second Defence, though the object uses are more naturalistic here). While the maze aspect of the puzzle is not in itself terribly challenging, having to reason about how to reach the necessary props adds both urgency and difficulty to the problem of assembling a trap.

As this puzzle is pretty much the entirety of the gameplay, it is doing all the narrative work. Dane’s constant pursuit keeps up the tension and reminds the player of the high stakes of failure. Many IF games use puzzles as gating devices to the big narrative moments, rather than rendering tense or anxious scenes as puzzles. (Combat puzzles are an exception, but there are relatively few of these in the IF canon.) Chemistry and Physics avoids this.

Meanwhile, the exploration teaches your character’s backstory. You were working (evidently) on a secret, illicit experiment with poor lab safety. It is not perfectly clear what exactly happened, but the opening text suggests that Dane is angry with you because of deaths associated with the experiment.

The implementation is not completely flawless. On one playthrough I managed to wind up on a blank screen for no discernible reason; more generally, I found it a bit frustrating trying to find the one location where I would be allowed to set down the box of explosives, since the text was not very specific about what I should be seeking. I found myself wandering around the lab trying to put the box down, then undoing a move when that failed in order to save time. This became a tedious and automatic process that somewhat undermined the suspense the game had otherwise done such a good job of establishing.

Despite these minor issues, however, Chemistry and Physics offers a multi-stage puzzle that is integral to its narrative, based on a combination of mechanics not usually seen together, and with high stakes for the outcome. Alongside ULTRA BUSINESS TYCOON III, this piece is also yet another rebuttal to the assertion that it’s impossible to make CYOA- or Twine-based puzzles. C&P’s world model includes inventory, room areas, timing, and NPC movement — many things one might associate with parser IF — and uses them to construct a tense challenge with unmistakable gameplay.

Creating the Meat Monster in Coloratura (Lynnea Glasser)

The Meat Monster puzzle is a puzzle with a one-move solution, low in extent and explorability but very high in surprise, originality, and narrative impact.

The player, acting as the deep-sea alien creature The Aqueosity, discovers a freezer full of meat. The Aqueosity perceives the meat as suffering fragments of life, cut off from the rest of the universe, unable to participate in its great Song. Fortunately, the player by this point has had a chance to familiarize herself with the Aqueosity’s unique abilities, which include the ability to influence the emotional and psychological states of other entities. (Almost all of the puzzles in Coloratura involve this palette of abilities, allowing for a very original set of solutions that is nonetheless grounded in its themes and setting.) The player has already had to soothe or agitate other entities before reaching this point. With that background, it’s possible to guess that the protagonist will be satisfied if the meat is warmed and calmed, and to perform the action that will make that happen.

So the solution to this puzzle is not intricate, not extensive, not especially ingenious, but it does require narrative comprehension and the synthesis of some past puzzle learning to accomplish.

But what really makes it a standout is the reward the player receives for doing it. The awakened steaks don’t simply (as we might have expected) achieve a state of inert tranquillity. Instead they form together into a living meat creature, which rampages through the ship, horrifying the human inhabitants, before jumping off the deck into the ocean. To the protagonist, this is a very good thing, the birth moment of a new kind of being, but as readers, we’re also able to imagine the human reaction of confusion and horror.

The whole of Coloratura works by requiring the player to think from two perspectives at once: the perspective of the Aqueosity, which provides the narration and the mechanical possibilities, and the perspective of the shipboard humans whom the Aqueosity needs to manipulate for help. Much of the power of the story comes from the terrible difference between what the characters think they are doing to one another and what they are actually doing; the humans and the Aqueosity repeatedly do one another harm through misunderstanding. The distance between how the two groups understand the world is demonstrated especially powerfully in this scene, which manages to be funny, scary, touching, and terrible all at once.

And, there is also a gap between what the player thinks she going to accomplish by typing in the command, and what she actually does accomplish. After all, the Aqueosity is not surprised or disturbed by the meat golem. The Aqueosity is satisfied and pleased. It is the player who is startled.

In the terminology of the (often reductionist but still sometimes very useful) screenplay guru Robert McKee, the Gap is the distance between what the protagonist wants and what the protagonist gets, creating a tension that drives the plot. Interactive narrative adds the possibility of player-centric gaps, in which it is the player who faces unintended consequences; but such gaps are often difficult to manage well. If the player’s action makes the game state worse, she may want to undo. If the game can’t proceed without the player committing to some mistake, she may feel cheated, railroaded, or punished for something that wasn’t her fault. This is why it’s easy enough to start a non-interactive horror story with the protagonist (say) summoning a demon using a magic amulet despite the warnings of other characters, but rather more difficult to set up a satisfying story in which the player has to perform the ill-advised ritual. The player-expectation gap is challenging to use because it often disrupts the player’s agency.

However, that is precisely the kind of gap we have here.

To describe what has happened to player agency at this moment, it’s useful to look to Stacey Mason’s distinction between affect, the ability to control the world in mechanically predictable ways, and diegetic agency, the ability to influence the outcome of the story. The player’s mechanical expectations are fulfilled, while her narrative/diegetic expectations are partially fulfilled and partially subverted. The Aqueosity’s unhappiness provides the initial motivation for warming up the meat, and in that sense the player gets what she wanted: the unhappiness is resolved. For this reason, the outcome doesn’t feel like a failure, a mistake, or something that the player might want to undo. It’s success with a startling twist.

It could be argued that this outcome — a thematically resonant narrative moment in which the player’s action leads the story in a surprising direction — is not inherently a puzzle feature at all. It doesn’t depend on challenges or on the player figuring anything out, and it is something that one could in other circumstances imagine occurring in a puzzleless interactive story. But because it is joined to a puzzle in this case, it gives that puzzle unusual significance and power.

Earning One Million Dollars in ULTRA BUSINESS TYCOON III (Porpentine)

One of the first things you encounter in ULTRA BUSINESS TYCOON III is a door that can be passed through only by a person who has One Million Dollars. Almost all of the game’s challenge involves figuring out how to gain the money that will get you past this one door.

There are a number of stages to this process. There are fetch quests where NPCs need particular objects, and puzzles that can be solved by pure exploration, which are fairly representative of the types of challenges that might exist in a game like this, even if they are shown here through text rather than through a graphical interface. These sub-puzzles are sometimes violent or disgusting and often demonstrate an unhealthy obsession with corporate wealth, which is of course the thematic point of this sequence.

But quite a few of the contributing puzzle solutions also involve metagaming in some fashion. At one point, you have to change the game’s difficulty settings to get past different obstacles. Elsewhere, you must look beyond the Twine piece itself to find the NFO document where Porpentine provides a “shareware code” to get past a particular puzzle. I myself didn’t find the relevant NFO file until I went looking for a walkthrough for the game — but the act of seeking a walkthrough on the internet is entirely appropriate as part of the experience of playing this game, rather than being the immersion-breaking act that it would be for most types of game experience. Having to do this also reinforces identification with the protagonist, who is not rich enough to be able to pay the shareware fee. These metagame-focused puzzles toy with the distinction between ULTRA BUSINESS TYCOON III the Twine game that you are playing, and ULTRA BUSINESS TYCOON III the graphical game that your protagonist is playing.

So while it is not in itself difficult to get through the door, doing so is a capstone on everything else that the player has done up to that point.

Meanwhile, the act of passing through the One Million Dollar door is, within the internal game’s terms, a complete let-down. The player is shown this door at the very beginning of play and allowed to build up all sorts of anticipation about it — the door has tremendous structural prominence — and yet UBTIII provides only a brief final message, an encouragement to buy more shareware games. There’s no amazing revelation about the state of the world, which is what the protagonist has been looking for all this time. It’s Be Sure To Drink Your Ovaltine all over again.

It is only in the context of the framing story that the win is narratively satisfying. It is at this moment that the protagonist breaks free from obsession with the game and is able to perceive and interact with the much more important things that are happening around her in the real world. By ceasing to care about the One Million Dollars, the protagonist can belatedly connect with someone else in the real world.