In this essay, I want to go over a variety of conversational systems that parser games can use. Emily Short has written many, many articles on this subject over time (see this page for a selection), and so long time followers of interaction fiction may find this redundant.
This article is part of my series advertising my upcoming Spring Thing game/Introcomp winner Sherlock Indomitable.
I’d like to discuss various ways to handle conversation in parser games. Conversation has typically been seen as a ‘problem’ in parser games, something to be solved. In choice games, there is no distinction. Conversation in those games is handled the same as gameplay, and is, if anything, sometimes easier to implement than other things like movement and puzzles.
Here are some of the systems used:
In many ways this is still the gold standard of IF. Parser games give off the illusion that you can do anything and get a response. While limited parser games get a lot of mileage out of showing how restrictive it really is, there’s still something exciting about a game that might understand anything reasonable you type.
This is hard, though. Three of the best-known purely conversational ask/tell games are Galatea, Alabaster, and Mirror and Queen. Galatea has hundreds of topics, around 60 endings, and is responsive to the order that you say things in, indicating some sort of memory, in addition to a Boston or other variables like the direction Galatea faces, her mood, etc. Alabaster was co-written by many, many people. Mirror and Queen understands something like 1000 nouns and organizes conversations on distinct tracks.
What these all have in common is that they are extremely labor intensive. To make a great conversational game, you have to constrain your setting, and then implement every noun that appears in that setting. There’s an art of name-dropping new people and objects into your responses to unlock new topics.
Benefits: Immersion, fits traditional parser gameplay style, wonder of discovery.
Drawbacks: Time-consuming to implement, frustration from not guessing the noun, and typing ‘ask about NOUN’ doesn’t say exactly what you’re about to say. Does ‘ask about dog’ mean ‘accuse Tom of killing the dog’ or does it mean ‘ask Tom what a dog is’?
Traditional menu-based conversation
This system, where you choose from a selection of conversational choices, was popularized early on with polished games like Photopia, and even now sees great use in games like Brain Guzzlers from Beyond. This is also, of course, the standard in choice-based games.
Benefits: Easy to program, easy to use, allows the player to know exactly what they’re saying.
Drawbacks: Breaks immersion in parser games, less of a feeling of freedom, interface style doesn’t match the rest of the game.
Hybrid: menu-based conversations with ability to change topics by keywords
This is essentially Emily Short’s Pytho’s Mask and Best of Three, and no other games that I can recall. In these games, you have menus of things to say, but typing in keywords can change your menu.
Benefits: Allows both player flexibility and discovery while letting the player know what exactly they are saying, and cluing the player on interesting things to say.
Drawbacks: Also combines drawbacks of both systems: menus can break immersion or be intrusive, while good keyword mechanics can be opaque and new keywords difficult to find.
Hybrid: Ask/tell with suggested topics.
This is used in a large portion of the block buster games that have come out in the last two decades (what I called Class 1 and Class 2 games in this post). Blue Lacuna, Counterfeit Monkey, Eric Eve’s games (and most TADS 3 games in general), etc.
In these games, there are suggestions on what keywords to use. These suggestions can sometimes be found by typing ‘topics’, sometimes found in gray (like Counterfeit Monkey), and sometimes they show up in separate windows (like Blue Lacuna).
Benefits: Provides a similar interface to the rest of the game while preserving the ease of keyword discovery. Some versions let you see what exactly you are going to say.
Drawbacks: Not that many, which is why it’s so popular. Less of the thrill of the discovery of new keywords, a bit of a feeling like you’re being led by the nose. Overall, a very effective strategy, though.
Constraining conversation in this way can allow for extraordinary freedom in coming up with responses. Spider and Web did amazing work with this system, and Gun Mute is surprisingly moving with the way it handles this.
Benefits: Easy to program, easy to use. Full immersion in the game.
Drawbacks: Doesn’t allow much player freedom.
TALK TO [Character]
In this system, a player types TALK TO whenever they meet someone. That person says a piece of dialogue. Repeated TALK TOs can get different answers.
This is popular in scene-driven or action-based games, where conversation only serves to move on to the next scene.
Benefits: Easy to program, easy to use. Doesn’t break immersion.
Drawbacks: Completely linear. Feels like ‘push button to play story’.
The conversation system for my Sherlock Holmes game:
For Sherlock Indomitable, I’m using the conversation system I developed in Halloween Dance and used in Color the Truth and Absence of Law.
This system is essentially a cross between ask/tell with suggestions and menus. The biggest difference is that this conversation system has been designed to bring conversation as close as possible to the rest of gameplay in parser games; that is, to make conversation essentially a medium-sized dry goods problem.
I do this by having topics be persistent in a sort of thought inventory. Standard ask/tell is naturally persistent; a keyword, once you know it’s implemented with one NPC, can be used with many.
Menus and suggested ask/tell are not persistent. A topic, once used, never comes up again.
By allowing topics to persist, my goal is to combine the ease of use of menus (by always knowing exactly what you can say) with the discovery/freedom of expression allowed by ask/tell (since you have to figure out who to say it too).
This system can be immersive, once you’re used to it, as it uses the exact format that inventory does. However, because it’s unusual, many players find it odd or frustrating.
One further feature of this method is that permanence of topics allows actions on topics. Topics can be examined to remember or to get an idea of exactly what you’ll say, and in my last 3 games, topics can be combined to create new topics.
Due to the large number of NPCs in Sherlock Indomitable, I’ve combined this system with TALK TO, so that Sherlock Reserves in-depth conversation for characters like Lestrade, Watson, and clients, while just TALKing TO all others.
Benefits: players know what they can say and what exactly they will say, allows for conversational puzzles and player freedom, allows for topic manipulation.
Drawbacks: requires a lot of response writing if every NPC reacts to every topic, and guidance otherwise to prevent players from getting the same rejection message over and over. Unusual, and, to be honest, somewhat clunky.
Overall, it seems that the most successful conversational method in games that aren’t purely conversation-focused has been ask/tell with suggested topics, closely followed by menus.
The success of my particular conversational system is yet to be seen. Color the Truth and Absence of Law were well-received, but several players have complained about the conversational system. My next game after Sherlock may use traditional ask/tell. But for now, there’s plenty of room for exploration.
For an especially interesting take on conversation in a choice-based game, try 10pm by litrouke.