CrimeGuess
Inspiration
I've always enjoyed detective stories and deduction games, but most of them are one-time experiences. Once the mystery is solved, there's little reason to return.
Since Reddit is built around communities, discussions, and theories, I started wondering what a detective game designed specifically for Reddit would look like. That idea became CrimeGuess.
Instead of creating another standalone web game, I wanted every mystery to live as an interactive Reddit post while giving players a persistent Detective Headquarters they could return to every day.
What it does
CrimeGuess is a daily detective game built for Reddit.
Players investigate mysteries by uncovering four hidden truths: the Culprit, Motive, Method, and Twist. Every investigation is its own interactive Reddit post, while Detective Headquarters acts as the central hub for continuing investigations, opening today's official case, revisiting previous cases, browsing archives, and discovering community-created mysteries.
Instead of selecting answers from multiple choice options, players freely guess words. The game responds with semantic-style feedback such as Ice Cold, Cold, Warm, Hot, and Very Hot, gradually guiding players toward the correct answer through deduction rather than luck.
How I built it
CrimeGuess is built using Devvit, React, TypeScript, Phaser, and Redis KV Storage.
The project is split into two main parts. Detective Headquarters acts as the permanent launcher and stores player progress, while every investigation exists as its own interactive Reddit post. This architecture makes it easy to support daily cases, archived investigations, and future community-created mysteries.
For the guessing mechanic, I wanted intelligent feedback without relying on external AI APIs. Instead of embeddings or language models, I built a lightweight offline lookup system using curated JSON datasets that group related words into different similarity levels. This keeps gameplay fast, deterministic, and completely free to run.
Challenges I ran into
The biggest challenge was making the experience feel native to Reddit.
Getting Headquarters, individual case posts, routing, state persistence, and navigation to work consistently across desktop browsers, mobile browsers, and the Reddit mobile app required several iterations.
Designing the guessing system was another challenge. I wanted players to receive useful semantic-style feedback without depending on paid AI services, so I designed an offline system that still rewards logical reasoning and feels satisfying to play.
What I learned
Building CrimeGuess taught me how to design around Reddit rather than simply embedding a web application inside it.
I learned how to structure multiple interactive posts, manage persistent player progress, integrate Phaser with React, and build gameplay systems that encourage players to return every day.
Most importantly, I learned that thoughtful game design and polished interactions often create a better experience than adding unnecessary complexity.
What's next
The current version includes official daily cases and the foundation for community-created investigations.
Next, I want to introduce automatically generated daily mysteries, AI-assisted tools for moderators, richer forensic mechanics, detective progression, achievements, seasonal storylines, improved moderation for community cases, and a much larger archive of official and player-created investigations.
My long-term goal is to make CrimeGuess a game that Redditors visit every day, not only to solve mysteries but to discuss theories, compete with friends, and build a community around detective work.
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