4 Ideas For Mystery-Themed Idle Games
Could a game where your detectives work while you’re away be the next big hit?
Happy Mystery Monday!
Today is the start of Steam's Idler Fest, which naturally made me curious: what would a mystery-themed idler game look like?
Although I personally don't play too many idle games myself, they are a highly popular genre, and one where mystery games are practically non-existent.
Yet, as you will see by the end of this article, mystery games actually combine nicely with the genre's mechanics. So there is a massive opportunity for developers to make some mystery games in this genre.
What are Idler Games?
For the sake of this discussion, we're going to lump together idle games, incremental games, and clicker games into a single category that we'll simply call "idler games" as Steam calls them. Each subgenre has small differences, but it appears that Steam has all three kinds of games in their Idler Fest. Many games are often a blend of these three subgenres anyway.
Incremental games are all about making incremental progress by doing the same, simple things over and over until new upgrades are unlocked. Clicker games are specifically about making incremental progress by clicking the screen, and idle games are about making progress without having to do anything at all (sometimes when the game isn't even running).
Making a Mystery/Idler Hybrid
My first observation, as silly as it sounds, is to recognize that a large portion of mystery games already use clicking on the screen repeatedly as a primary mechanic. Whether it's point-and-click adventure games or escape games where you pixel-hunt for clues on-screen, or even just linear visual novels where you click repeatedly in order to read the next page of text, mystery games are already doing a whole lot of clicking.
The only thing missing is tying those clicks directly to incremental progress.
By "incremental progress", I simply mean "making a number go up." Clicks in these games act as a type of currency. As your clicks increase, you gain more currency, which you can then use to buy automations to do the clicking for you. Eventually, you no longer need to do any clicking yourself, and the clicker game essentially turns into an idle game.
For the most notable example, take a look at the massively popular Cookie Clicker, if you haven't already.
Most clicks in mystery games aren't about incrementing a number. Instead, they are usually about interacting with the environment — whether that means hunting for clues or talking to characters or something else entirely. So if we want to make an idler/mystery hybrid, we have to really re-think the way we approach mystery game design.
But, like I said at the beginning, these two genres actually fit really well together.
Going back to the linear visual novel example, games like Umineko, Detective Butler, and Reaplaced are all about solving a mystery, despite having practically zero gameplay. Maybe these games already count as "idle" games if you have the text scroll automatically, letting the game "play itself."
However, those kinds of detective games usually at least have some kind of system for keeping track of clues, characters, and other important information. The player can review these notes at any time to think up new theories in response to new information. So the real gameplay — theorizing answers to the mystery — takes place mainly inside the player's head.
The natural next step in this line of reasoning is to make that kind of evidence-collection system dependent upon incremental gameplay (making a number go up) rather than scrolling through walls of text.
The most basic example is to take a classic problem of point-and-click games — pixel-hunting — and transform it into a core gameplay mechanic. Just click everywhere on the screen in order to gain "investigation points", and after gaining enough of them, you can "purchase" a new clue from the crime scene. Or maybe you could use those points to buy a new piece of detective equipment, or hire an assistant, to click for you.
Boom, you now have a mystery/idler game hybrid.
4 Ideas for Mystery Idle Games
There are, of course, many more interesting ways to design a mystery-themed idler game. The whole concept of an idler game is infinite scale, and you could certainly scale things up by automating an entire detective agency by just clicking. So this article only just scratches the surface of what's possible.
However, I would like to leave you with a few more examples (inspired by existing idler games), just to get your head thinking about the possibilities, and maybe even inspire you to make your own.
1. Crime Scene Excavators
You’re running an excavation site, uncovering lost artifacts that reveal a forgotten mystery.
Start with basic tools, then upgrade to ground-penetrating radar and AI analysis.
Find ancient relics, encrypted texts, and strange anomalies.
Piece together how past civilizations lived and what they were hiding.
Black market collectors and governments might try to steal or suppress your findings.
What was buried, and why was it hidden?
2. Mystery Academy
Train to become a world-class detective, mastering different investigative disciplines.
Begin by training in observation, interrogation, and forensic techniques.
Level up skills such as lie detection, surveillance, cryptography, and forensic science.
Specialize and choose a path: homicide, cybercrime, corporate espionage, or psychological profiling.
Automate investigations by sending junior detectives to collect clues while you work on bigger cases.
Eventually, you can unlock access to cold cases, missing persons, and criminal conspiracies.
3. Cryptid Terrarium
You’re a cryptozoologist running a secret research facility, caring for and studying legendary creatures.
Find evidence of cryptids in ancient myths and blurry photos.
Use bait, hidden cameras, and research teams to locate and capture rare creatures.
Upgrade enclosures to accomodate special habitats, climate control, and secrecy measures.
Study behavior to uncover hidden traits, unknown abilities, and potential dangers.
Decide their fate: do you keep them secret, reveal them to the world, or weaponize them?
4. Mysterious Paperclips
Train an AI to solve crimes while preventing it from exterminating all of humanity.
Process digital evidence by decrypting files, scanning dark web transactions, and tracing anonymous accounts.
Train the AI to identify deception, human motivations, and criminal patterns.
Expand from solvig digital crimes to deploying fully autonomous robots that stop physical crime.
Detect ethical dilemmas and train the AI to make ethical decisions.
Balance the goal of decreasing crime without letting the AI go rogue.
Conclusion
Idler games are very popular, and can potentially be a great way for mystery games to reach a wider audience:
Idle mechanics fit perfectly with long-term investigations.
Players can uncover secrets slowly, making discoveries more rewarding.
Automating detective work feels natural, like building an investigation team.
A mystery idle game could be infinitely replayable with procedural cases.
Just like when I wrote about farming games and cooking games, I'd love to spend time making a mystery-themed idler game, too! But anyone is free to take these ideas and turn them into a real game, because I would love to play them.
And if you have any ideas of your own, feel free to let us know in the comments, because I would enjoy hearing them!
Thanks for reading!
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