Attention: since I published this post, I have discovered that what I call here a Logic Puzzle actually fits better the description of a Logic Riddle. Keep that in mind when reading this blogpost.
I already explained in an earlier post that we don't have the luxury of monitoring player's speed and coordination in the genre of gamebook adventures,
so the only gamer input left available for us to measure is the player's logic. I wrote quite a bit about giving control over the outcome into the hands of our players through Logical Conclusion Choices and I'd like to see more gamebook adventures do some of that.
Now is the right time to mention another input mechanic for testing performance that I feel has been underused by game designers: Logic Puzzles. As far as I know, the first author to use it was Michael Mindcrime in his Bulgarian gamebooks back in the early 90's. He used very simple, but at the same time, very entertaining Logic Puzzles in his books and they made him quite famous among the fans in that country.
As you will read in the final version of our example Short Gamebook Adventure at paragraph 19 (right after finding the secret passage to the mausoleum), the reader is given the following dilemma:
Scanning the insides of this old Mausoleum, your eyes suddenly stop on three levers sticking out of the dark covering the far wall. A sign above them says “One of these shuts the HellGate closed”. Naturally, the other two would let all the hell creatures enter this world and turn it into an infinite doom. As you are getting closer, you see that there are words inscribed in each one of them. The inscription on the first lever reads: “Lever 3 is lying. I am the only one to close the HellGate”. The second one says: “Lever 1 shuts the HallGate and Lever 3 statement is false”. The words on the third lever state: “I am the only one to shut the HellGate closed”. You are not sure how, but you are certain that only one of those says the truth. Which lever would you pull? Go to 21 if you choose to pull the first one. Go to 22 if you prefer to pull lever number two or turn to 23 if you decide to trust lever number three!
The way to break this logic puzzle is to play out each one of the possible scenarios. According to the text, it is clear that only one of the levers states the truth.
1. If the first lever statement is true, the second one would be true as well and therefore we have two of them saying the truth. This result is already in direct conflict with the main condition of the logic puzzle that only one of the lever statements can be true.
2. The same logic could be applied if we test the statement of Lever 2.
3. If Lever 3 says the truth, the other two are incorrect. That fits the logic puzzle condition of only one lever statement being true. Therefore Lever 3 is the one that shuts the HellGate closed.
That all makes sense and it looks great, right? However, before I started writing this post, I wondered for a very long time how to create a Logic Puzzle like this. It took me a long while, but it downed on me that the easiest way to write such thing is to start with all three levers having true statements such as: Lever 1: "Lever 3 shuts the gate"; Lever 2: Lever 3 shuts the gate; Lever 3: I am the only one to shut the gate. The requirement I chose to fit in this puzzle was to have only one of them stating the truth, so I had to change the statements of the first two to be false.
When creating such Logic Puzzle, it would be very easy to miscalculate and make it very confusing by having more than one possible correct answers, so make sure you double and triple check each one of the options for inaccuracies. There is nothing more frustrating to the player than to be stuck with two true lever statements without a clear way to tell which one is the correct one.
Also, keep in mind that you can use many different kinds of logic puzzles in your games. Here is another great example taken from the Michael Mindcrime book "The Dark Side of Earth": Guess which picture is covered under the hand placed over the third cube! If you decide to test your logic, check out the correct answer to this puzzle at the end of the post
I hope that you get the main idea here. Test the reader from time to time and reward them for good performance or punish them if they choose unwisely. I promise that your readers will truly appreciate the good challenge and that will give them the satisfaction of having more control over successfully reaching the ultimate ending of the adventure.
Beware! While this game mechanic is great, because it keeps the control of the outcome entirely in the player's hands, be careful to not overuse it. I'd say there should be no more than one of these logic puzzles per 50 paragraphs in the adventure. If the player finds himself trying to break similar encounters way too often, he will become distracted from the main storyline plot and he will quickly get bored, because of losing perspective over the final goal of the adventure. Ideally, I'd use this kind of mechanic at the end of the game or at some extremely important encounters during the story.
The correct answer to the logic puzzle above is 'the shovel'.
I believe that this concludes your Gamebook Practice experience that focused on the challenge of keeping the player in control of the adventure through testing their logic. Next, I am going to keep working on Gamebook Theory and talk about the alternative to the Diverging Diamond diagram: The Disrupted Infinity Gamebook Adventure Approach.