Adventure game puzzles: unlocking the secrets of puzzle design
First posted on 05 December 2008. Last updated on 28 June 2010.
About the author
Mark Newheiser is a graduate of UCSD with a master's degree in computer science and a lifelong adventure game enthusiast. When he is not designing or dissecting complex systems, he enjoys giving the other half of his brain a workout and participating in the worlds of sci-fi, fantasy, and gaming.
For more information, visit Mark Newheiser's Home Page.
For a lot of games, you can figure out most of what you need to know about them from simply looking at an in-game screenshot or watching a gameplay trailer. With a quick glance at the head-up display and the quality of the graphics, you can get a good sense of what kind of monster killing mayhem you will be engaging in and what kind of experience you will likely get from playing the game. Judging the quality of such games often comes down to how well the game manages to simulate its world and how engaging and rewarding the gameplay proves to be. The basic experience of playing that game can be described well enough through a brief preview.
Adventure games are different—in that the core features of gameplay cannot be effectively evaluated without actually playing it or giving so many details away as to detract from the experience of playing the game. In many respects, the quality of an adventure game depends upon the quality of its puzzles, whether they are ingenious and rewarding or just frustratingly illogical. Having been told an explanation to how a puzzle works means you will never be able to play it as intended, since a big part of the experience is the enjoyment of figuring it out for yourself. You can evaluate the art, voice acting, and even the story or humor present in an adventure game to a certain extent without diving too deep into it, but an adventure game with terrible puzzles can make all those other elements irrelevant, since you likely will never have the patience to finish the game in the first place.
In this article, I will be taking a closer look at the various types of adventure game puzzles, how they relate to the gameplay, and even how some of these basic forms relate to other game genres.
A point that Ron Gilbert, co-creator of Monkey Island, has made about adventure game design is that for most puzzles the player should be presented with a problem before the solution is apparent (1). Rather than wandering around with a bucket of water in your pocket and waiting for a puzzle to present itself that could conceivably allow for its use, you should see the raging fire first and then start looking for possible solutions, rather than idly looking for possible problems. In other words, you should see the lock before the key. With that in mind, I propose a taxonomy of adventure game puzzles by dividing them up into 2 categories: puzzles that are entirely self-contained from when the player first approaches them (hereafter called self-contained puzzles), and puzzles that require some external "key" to solve (hereafter called "key" puzzles). Both categories can be further broken down for additional classification.
Self-contained puzzles
Self-contained puzzles can be categorized into 3 types: interaction puzzles, which depend upon the player performing some basic interaction; mini-game puzzles, which depend upon the player solving some self-contained game; and riddle puzzles, which depend upon the player providing the correct answer to a posed problem.
Interaction puzzles are puzzles that can be solved simply by interacting with an object in the game with a verb that dictates an action. This may involve recognizing that an object could be useful and picking it up, being duly rewarded with a few points and a triumphant fanfare, or an act as simple as opening a door, pushing a rock out of the way, or performing any action that the player is capable of doing with the game's basic commands. An important note is that the game's interface can go a long way to affecting how trivial or tricky this type of puzzle is, with a parser finding the appropriate verb for interaction may require some serious thought, whereas in a point-and-click adventure game there is often only a single choice. Identifying objects to interact with is a trivial task in classic adventure games from LucasArts that make all objects explicit to the player, in contrast to classic adventure games from Sierra where the player has to search for hotspots and guess what constitutes an actual object from the game's point of view (2).
Mini-game puzzles are a step above interaction puzzles in complexity. Rather than involving a single basic interaction, they generally require arranging a bunch of elements into a particular configuration or performing some set of actions in sequence. Examples include solving sliding tile puzzles, connecting pieces of a circuit to form a complete path, or arranging a set of books in alphabetical order. The key features of this kind of puzzle are that it is self-contained (no external clues or items are necessary to solve it) and that it is generally based around manipulating controls to achieve a particular pattern. By contrast, if the combination that you are meant to achieve in a puzzle is not self-evident or has to be figured out from some external source, this is an example of a pattern puzzle (to be discussed later).
A common criticism that has been leveled against this type of puzzle is that since it does not interact with the player's inventory or the rest of the game world, it can feel like an unnecessary lengthening of gameplay (3). Even so, it remains a popular form even across other genres; many role-playing games and action adventure games make significant use of this style of puzzle, with block puzzles and the like serving to break up pieces of action oriented gameplay.
What starts out on 4 legs, then goes around on 2, and then travels on 3 legs? If your answer is "man", then you have just solved a classic example of riddle puzzles dating back to Oedipus Rex. Riddle puzzles are puzzles in which you are expected to provide a particular answer based upon clues presented. It may be seen as a special case of interaction puzzles involving more complicated verbs or a form of mini-game puzzles where the combination you are supposed to figure out is a specific answer. However, it is worth categorizing these types of puzzles separately, since there is a significant difference between the common cases of coming up with an answer compared to moving a set of game objects into some predetermined arrangement. Riddle puzzles seem to have been more prevalent in the era of games where text parsers were common, since they require a break from relying on your basic verbs for interacting with objects and generally switch to some interface that lets you input a textual answer. As with mini-game puzzles, if the riddle requires some additional information the player is expected to gather elsewhere to solve, it is not really an example of a riddle puzzle but a pattern puzzle. You can simulate a puzzle of this type by giving the player a fixed list of choices, but without the open-endedness of providing your own answer it is more easily cracked by brute force fiddling.
All these types of puzzles produce a certain satisfaction since players are able to take their time and solve them on their own. This is a very different experience than being initially stumped by a puzzle and returning later triumphantly with the "key" in hand. For example, the Professor Layton series features puzzles entirely of the latter types of self-contained puzzles. All the puzzles in the series are isolated challenges, usually requiring the player to solve a riddle by giving a definite answer and occasionally requiring the player to complete a mini-game. Since each puzzle is solved independently of the others, this avoids the classic adventure game dilemma of never being quite sure if you have everything you need to tackle a puzzle and worrying about what you may have missed. The only drawback is that it does not allow for some of the more complicated interrelated puzzle solving sequences which other styles permit.
"Key" puzzles
As it has already been discussed, self-contained puzzles can be cracked from the moment the player approaches them, either through the game's basic method of interaction, a more complicated series of actions to solve a mini-game, or by answering a riddle.
"Key" puzzles, by contrast, are puzzles that require some external help and can be categorized into 3 types: inventory puzzles, which depend upon the player obtaining the right items; pattern puzzles, which depend upon the player learning a key piece of information, often to figure out some pattern the player subsequently needs to input; and implicit information puzzles, which depend upon the player making an internal change to the game's state, most commonly by making the player's character aware of some new information that allows the character to perform new actions.
Inventory puzzles are a longstanding staple in adventure games—an approach to puzzle play that rewards the player for being an obsessive packrat and devotedly trying to mash every pair of items in the game together in the hopes they will unlock a hidden use. This type of puzzle depends upon the player having the right inventory item in possession, so that it may be used on the correct person or object in the environment. This can mean using a literal key on a literal lock, using a saw to cut down a tree, putting on a cloak at the right time, or throwing a piece of cheese into a machine (if the game designer is feeling particularly sadistic). From a design perspective, inventory puzzles can be a convenient way to tie a series of related puzzles together, by ensuring that the item a player needs to complete a puzzle is given out after the solution to another puzzle, thus guiding the player towards unlocking a series of related puzzles bit by bit.
In their most abstract sense, inventory puzzles can be found in a number of other game genres, such as a role-playing game requiring a hammer to break apart stones to reach certain areas, so that once the player has that hammer all such similar areas become accessible. Adventure games typically differ in their employment of inventory puzzles by having a large number of items, most of which have only a single use, whereas role-playing games tend to contain a much smaller number of items, each of which has an extremely generalized use in the game world.
Pattern puzzles are puzzles that depend upon the player obtaining a key piece of information which makes the puzzle solvable. This does not mean that the game simply provides clues to make inventory puzzles easier to figure out—most often for pattern puzzles, the solution is literally a piece of information. An example is figuring out the password to a safe by finding it written in a desk drawer, or learning the correct configuration to a circuit by finding a blueprint. In terms of literal game mechanics, the player's character may always have been capable of solving these puzzles, but the player has no chance of guessing or arriving at a solution without learning the necessary piece of information. These puzzles can also be more complex and require correlating multiple pieces of information, such as finding a series of colors printed on a floor, learning how colors correspond to letters, and then using the translated version of those colors as a password.
Implicit information puzzles can be seen as an alternative to pattern puzzles, where the information received is communicated by the player's character rather than the player. With pattern puzzles, if a player happens to have played the game before and knows the combination to a safe, the player may be able to crack it immediately without doing the necessary work to track down the combination. However, if the game chooses to represent the safecracking as an example of implicit information puzzles, then solving the puzzle depends upon the player taking the necessary steps to make the player's character aware of the answer. This type of puzzle can also be seen as an alternative to representing all "keys" to puzzles explicitly as inventory items, such that after beating a puzzle the player's character may receive some new information and the game may mark some internal change to the game's state that allows for another action which otherwise could not have been performed. Rather than approaching every puzzle from the perspective of what items can be found or used, the player has to think in terms of what new information can allow for new actions to be performed, and what the player has learned that can be communicated to another character who may be able to help.
This can sometimes lead to some gameplay frustration, such as when the player feels confident in knowing what to do but cannot progress until the player's character has had enough conversations or seen enough to be fully clued in. On the other hand, if this is done well, it can keep the player more closely tied to the character's own motivation and knowledge of a scenario. Taken in its most general sense, this type of puzzle can simply represent any time the game's internal state changes as a result of a player's actions and makes further progress possible, which can lead to all sorts of unusual behaviors such as new areas becoming accessible because the player has finally got around to talking to an innkeeper.
A final note is that while these categories represent the basic ingredients of puzzle solving, a single puzzle from the game's point of view may involve a composition of a number of these elements. Some pattern puzzles may require collecting a number of inventory objects and then arranging them in the right order. Some inventory puzzles may require using a number of objects to perform a series of actions in sequence, wherein failing to do them in the right order will force a restart, and an inventory puzzle may require using a number of objects in parallel to complete a recipe, such that the puzzle is not considered solved until all the ingredients are present.
Analysis of puzzle solving
An interesting point to note is that whereas mini-game puzzles and pattern puzzles often have to be completely logical so that they can have an unambiguous solution or arrangement, riddle puzzles, inventory puzzles, and implicit information puzzles can all be prone to leaps of illogic or tortured reasoning. When done well, however, they can be a welcome creative break by involving some lateral rather than linear thinking. The potential pitfall to these puzzles is that while the correct arrangement of a pattern puzzle may be the only solution that makes sense, the player may be able to come up with all sorts of item usage scenarios that make more sense than those the designers have envisioned; in such cases, the player may be left feeling like the action they are expected to perform is not reasonable. Implicit information puzzles can make the mistake of leaving no clue that the player is now able to perform a task which the player was not able to do before and obligate the player to exhaustively try out their available options every time progress is made. Any fan of riddles is probably aware how such puzzles can sometimes be obscure or ambiguous in their solutions, and many varieties of puzzles are guilty of relying on some specialized knowledge not all players may possess, such as a knowledge of history or mythology or a familiarity with mathematical numbering systems for some types of pattern puzzles.
There are a few types of puzzles that do not fall neatly into this classification, such as mazes. If a maze is solved in isolation to progress in the game it can be classified as an example of mini-game puzzles, but many games have their relevant areas connected through maze like environments that sometimes require extensive mapping, which I prefer to characterize as a feature of how the game world is laid out rather than an explicit puzzle. Of course, this whole classification excludes puzzles such as timing based puzzles or puzzles that integrate real-time physics; the Half-Life series features many such puzzles where the player is expected to pile up boxes to reach a platform or weigh down a lift to reach a lower level. In the most abstract sense, these types of puzzles may still depend upon the player's basic verbs of interaction or make use of items and information, but the means by which they are solved sets them apart from the puzzles commonly featured in adventure games. Lastly, there is the subset of puzzle games that relies on real-time pattern matching and arrangement, as in games such as Tetris. While these games share some similarities with types of mini-game puzzles which use similar styles of arrangement, the inclusion of a real-time engine or procedurally generated puzzles significantly changes the nature of the activity. A classic adventure game puzzle is conceived in advance by the designer to be worked through at the player's own pace; a puzzle game is more often a system for generating puzzles which test the player's pattern finding skills in real-time.
Even among adventure games there is significant variety in the types of puzzles represented. The Myst series of games relies almost exclusively on mini-game puzzles and pattern puzzles, with only a few rare instances where the player has to carry and use an item to progress. In contrast to a reliance on logic based puzzles, most adventure games from LucasArts and Sierra get the most mileage out of inventory puzzles, with occasional variations such as using objects in the inventory in isolation or with each other, or navigating conversation trees as a means of interaction. Some "escape from the room" online adventure games make small use of inventory puzzles, but the bulk of the challenge in these games is in simply searching the room and finding all the objects that the player can interact with.
The types of puzzles included greatly affect how the player is expected to play the game—the original Myst comes with a notebook to help the player keep track all the necessary information to find the solutions to the game's many pattern puzzles. The later Myst sequels include an in-game system of taking photographs and writing notes to simplify the management of all the information the player needs to know. Games that make heavy use of inventory puzzles have to take special care to manage the "bag of tricks" the player has at disposal for solving the puzzles, clearing it out of unnecessary filler at times and making sure the player can always retrieve any item that may be needed. Any game that relies on interrelated rather than isolated puzzles has to take special care to manage the scope of what the player is expected to explore without being overwhelmed, and it is sometimes necessary to cut the player off from past areas in order to keep the scope of the game manageable. Another problem with puzzles whose solutions depend upon each other is that if the player fails to solve a single piece of an interrelated puzzle network, gameplay can simply come to a halt. A technique to deal with this problem is to make a number of puzzles optional or provide alternate solutions with varying levels of reward to ensure some form of progress can always be made.
Puzzle solving in all of its various forms is probably as old as games themselves. Rather than making strategic choices, testing reflexes in real-time, or engaging in competitive activities, the challenge is to come up with a precise solution. As this article has discussed, taken in the most abstract terms, the solution can be self-evident and obtained independently from the game world, or it can depend upon the player utilizing information, explicitly managed items, or implicitly managed information. Even as the basic forms of these puzzles have begun to seep into other game genres, the adventure genre still represents the most interesting exercise of that form, offering up challenges in both deciphering and designing elegantly conceived puzzles.
References
1. Gilbert, R. Why Adventure Games Suck. http://grumpygamer.com/2152210
2. Newheiser, M. Searching Under the Rug: Interfaces, Puzzles, and the Evolution of Adventure Games. http://www.strangehorizons.com/2008/20080804/newheiser-a.shtml
3. Metzler, S. Where Have All the Puzzles Gone? (Part I). http://www.metzomagic.com/showArticle.php?index=851