Special Design Considerations

The following special considerations apply especially to adventure games , although there is some crossover with RPGs as well.

Conversations with NPCs

From the original Adventure onward, adventure games have always faced the problem of how to create realistic NPCs in the game world. RPGs have this problem, too, but in most of them, the NPC's conversation is defined by the role to which he's assigned: blacksmith, healer, tavern keeper, and so on. The player doesn't expect to be able to discuss arms and armor with a tavern keeper (although the games might be more interesting, and certainly less formulaic, if he could). But because adventure games are interactive stories, players expect the characters in them to be more human and less mechanical.

A good many games have tried to sidestep the problem entirely by setting the game in a world where there are extremely few people or none at all. This certainly creates a mysterious atmosphere, but it's suitable only for a limited range of stories. Imagine how Rick's bar in Casablanca would feel if it weren't full of people drinking and gambling. A world with no people in it is artificial and sterile.

A few early text-based games tried to implement parsers that could understand limited English sentences as typed by the player, but these seldom succeeded. You got either an NPC saying "I don't understand that" when you had asked a perfectly reasonable question, or an NPC whose answers weren't quite to the point, giving the impression that he was drugged or mentally ill.

Scripted Conversations

In the end, most adventure game designers gave up on trying to create the impression that you could talk to anyone about anything and devised the scripted conversation , a mechanism that has become the de facto standard for both adventure games and RPGs. A scripted conversation is a branching-tree structure in which each node represents an opportunity for the player to select one of several fixed lines to say from a menu of choices (see Figure 15.12). Depending on which line the player chooses to say, the NPC responds appropriately, and the conversation moves on to a new node in the tree. The contents of the menu change as the conversation progresses; as the NPC says things the player hasn't heard before, the player gets opportunities to ask for elaboration, end the conversation, or switch the subject to a different topic. Another common choice is "Tell me again about ," which enables the player to return to an earlier point in the conversation and go through it again, if he didn't pay close enough attention the first time.

Figure 15.12. The conversation menu in The Lost Files of Sherlock Holmes .

Benefits of Scripted Conversations

Although the scripted conversation forces the player to say only the things in the script, it does produce natural-sounding conversations, in which the sequence of remarks and replies is plausible. It also gives you, the designer, a way to illustrate both the avatar's and the NPC's character through something other than their appearances . You can write their lines in such a way that you give them distinct personalities of their own. For example, Guybrush Threepwood, the hero of the Monkey Island games, is a wise guy type who seldom takes anything seriously. The character's vocabulary, grammar, dialect , and ”if the game has recorded audio of the conversation ”tone of voice and accent are all important cues.

In addition to letting the player discuss a variety of topics with a given NPC, the menu system allows the player to choose a variety of different attitudes in which she says the same thing: aggressive , deferential, formal, or flippant, for example. The NPC can then respond to each of these in whatever way his character dictates. For example, a powerful character who brooks no nonsense might be offended by wisecracks and refuse to talk to the player anymore. (If you do this and the NPC's information is vital to the plot, make sure that either the NPC gets over his snit after a while or there's some other way for the player to obtain the information.)

The scripted conversation is not merely a mechanism for giving the player information, however. It's a real part of the gameplay, and the player's choices can have a distinct effect on the progress of the game. For example, an NPC could ask the player to entrust him with a valuable secret. The player's decision, whether to tell or not to tell, could have far-reaching consequences. The player has to choose based on her assessment of the NPC's character ”to which you, the designer, must provide clues.

Mapping

When playing text adventures , players usually needed to make a map for themselves as they went along. Because the rooms were not physically modeled but were only described, it was difficult for the players to remember how the rooms were related to one another. A lot of text adventure worlds were also purposefully illogical, so a map was really important for keeping track of the relationships between different areas.

With the arrival of graphic adventures, mapping became less critical because the graphics provided cues about where the player was and how his current location related to other areas in the world. However, we think it's a good idea to give the player a map. A few games deliberately deny the player a map to make the game more difficult, but this is usually poor design ”an obstacle that slows down the player without providing any entertainment value. There's not a lot of fun in being lost. If you force the player to make his own map, he has to constantly look away from the screen to a sketch pad at his side; that's a tedious business that rapidly destroys suspension of disbelief.

The map that you give the player doesn't have to be complete at the beginning of the game; it can start out empty and be filled in as the player moves around, a process called automapping. The player should be able to refer to his map conveniently at any time. It's also a good idea to give the player a compass to tell him which direction he's facing .

Automapping destroys the challenge imposed by mazes, but we think mazes are one of the most overused and least-enjoyed features of adventure games. Unless you have a good reason for including a maze and can construct one that's really clever and fun to be in, don't do it.

Journal Keeping

Another common feature of adventure games ”one that is conceptually similar to automapping ”is automatic journal keeping. The game fills in a journal with text as the player goes along, recording important events or information she has learned. If the plot is convoluted or there are large numbers of characters in the game, the journal is an invaluable reference tool for the player. Let her call it up and look at it at any reasonable time (though not, perhaps, while hanging over the edge of a cliff or being interrogated by a mean bad guy). As with conversations with NPCs, the journal gives you an opportunity to define the avatar's character through her use of language.

A Few Things to Avoid

As adventure games have evolved, their designers have created many different kinds of puzzles and experiences for the player. Some of these are extremely clever, such as the insult-driven sword fight in The Secret of Monkey Island . A good many others, however, proved to be only tiresome time wasters , obstacles that added no entertainment value to the game.

Puzzles Solvable Only by Trial and Error

If you give the player a puzzle that has a fixed number of possible solutions of equal probability (in effect, a combination lock), but no hints about which one is right, then the player simply has to try them all. The Infocom text adventure Infidel included a puzzle like this: Four statues of Egyptian goddesses had to be lined up in the correct order, but there were no clues about what it might be. The player simply had to try all 24 possible combinations and keep track of the ones she had already done. There's not much fun in that.

Conceptual Non Sequiturs

This is a variant of the trial-and-error puzzle, a problem whose solution requires thinking so lateral that it's completely irrational. A conceptual nonsequitur is something along the lines of "Put the lampshade on the bulldozer" or "Sharpen the headphones with the banana ." A few games try to get away with this by claiming that it's surrealism, but true surrealism is informed by some kind of underlying point; it's not just random weirdness.

A variant of this is the opposite-reaction puzzle, one whose solution turns out to be the exact opposite of what you'd expect. You could give the player a rubber dagger and then have it turn out to be a deadly weapon after all. In the original Adventure , the player could drive away a menacing snake by releasing a little bird from its cage. Fortunately, at this point in the game, the player didn't have many options, so he usually found the solution soon. But unless you design an entire game on this principle, it's just an annoying gimmick.

Illogical Spaces

Illogical spaces were a classic challenge in text adventures. If you went north from room A, you got to room B, but if you went south from room B, you didn't go back to room A. Their modern equivalent is teleporters that give you no idea of where you have teleported to. The player simply has to wander around taking notes until she can figure out the relationships among the various locations. Unless you offer some clues, this is another problem that can be solved only by trial and error.

Puzzles Requiring Outside Knowledge

Many adventure games rely on some occasional oddities , especially for comic effect, but the player must have a realistic chance of figuring them out. If a game requires information from a source other than itself, it's unfair to the player. For example, Haunt had puzzles that could be solved only if the player was familiar with the 1960s-era cartoon series Beany and Cecil ("Help, Cecil, help!") and with the movie Monty Python and the Holy Grail . It didn't really matter because Haunt was distributed for free and was mostly a joke anyway, but in a commercial game, such puzzles would be unreasonable unless you explicitly made it clear that knowledge of trivia was required. If you want to make humorous references to popular TV shows, movies, and so on, do them in narrative or in an NPC's conversation rather than as solutions to puzzles. Beware, though: Cultural references age very quickly and will make the game seem dated after a few years .

You have to be even more careful when developing games for foreign markets because other countries don't always have the same idioms. For example, the action "Wear the lampshade on my head" could cause other characters in the game to assume that the player's avatar is drunk, which might be desirable in the context of the story. However, wearing a lampshade as a sign of drunkenness is an American cultural idiom that might not be understood in Japan, for example. Again, it's okay to make cultural references in your game; just be careful about requiring the user to understand them to win.

Click-the-Right-Pixel Puzzles

A few adventure games with point-and-click user interfaces require you to click on a tiny and inconspicuous area of the screen to advance the story, for no particular reason except that it's difficult to find. This is lazy design ”a cheap way of creating an obstacle for the player without any entertainment value.

Backward Puzzles

A backward puzzle is one in which you find the solution before you find the puzzle itself. For example, you find a key, but you don't know of any locked doors. However, you carry it around with you all the time, just in case. When you do eventually find a locked door, you immediately have the solution, which means it's not much of a puzzle. It's not always possible to prevent the player from finding a solution before he finds a puzzle because the solution has to be available, but it can be inconspicuous ”for example, a poster on a wall full of posters , or an object in a trash can. Be aware, however, that "inconspicuous" is not the same as "obscure" or " nonsensical ." If the key to a puzzle involves finding a live monkey, the monkey shouldn't turn out to be locked in a freezer.

Too Many "FedEx" Puzzles

A FedEx puzzle is one that you solve by picking up an object from one place and bringing it to a different place, as if you were a Federal Express driver. Of course, carrying objects around until you find a place to use them is a common feature of adventure games, but some games consist of little else. This gets dull after a while, especially if the solution to a puzzle consists only of fetching and carrying without any lateral thinking or other activity. Liven up the game with a variety of puzzles and tasks . It's fun to include objects that have a variety of different uses, such as Indy's bullwhip in Indiana Jones and the Infernal Machine , or objects that are left over from one puzzle but have a part to play in another.

Adventure Game Worksheet

When beginning the design of an adventure game, consider the following questions:

1. Who is the central character in the game, the player's avatar? What is the avatar's sex? (For the purposes of this worksheet, we'll assume that the player is male and the avatar is female .) What does she look and sound like? What are her personal qualities, strengths, weaknesses, interests, likes, and dislikes? What sort of vocabulary and grammar does she use? What are her ethnic , social, religious, political, and educational backgrounds? What is her personal history? What is her family like?

2. What is the story of the game? What is the avatar's ultimate goal? What will occur at the dramatic climax? What things must she collect, learn, or achieve for the dramatic climax to take place?

3. Where does the game take place? What sort of a world is this? Is the player free to move around these areas continuously throughout the story, or do one-way elements prevent him from returning to earlier areas?

4. What other characters are in the game? What functions do they serve? How do they look and act? How do they respond to the avatar? Can she affect their moods and attitudes?

5. How is conversation implemented? What consequences can arise from it? Can the player choose a variety of attitudes in which to speak?

6. What kinds of puzzles are in the game? What obstacles will the player encounter, and what actions will he be able to take to overcome them? Is this a pure adventure game or an action-adventure? If it's an action-adventure, what are the action elements like?

7. What graphics technology will be used to display the world? 2D backgrounds? Real-time 3D? How will this affect the look and richness of the world?

8. What perspective will the player have on the game setting? Context sensitive? First person? Third person?

9. What is the user interface for moving the avatar around the game world? Will it be point-and-click, direct control, or some other mechanism?

10. How does the player recognize active objects in the world? How does he command the game to manipulate them? What verbs are available for each object?

11. Is there an inventory, and, if so, how is it displayed and used? How does the player pick things up and put them down again? Can objects be combined or used together? How is this handled?

12. Does the player need a map? If so, will it be static or maintained automatically?

13. Should the game keep a journal to help the player remember things?