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Jonadab Uroh
Jonadab Uroh

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Solstice Assassin

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June Solstice Game Jam Submission

This is a submission for the June Solstice Game Jam
(https://dev.to/challenges/june-game-jam-2026-06-03)

What I Built

I built Solstice Assassin, a tactical stealth-action game set inside a collapsing digital mainframe.

You play as Alex, a self-aware digital anomaly trapped inside the Solstice Grid, a secure virtual system originally created by Alan Turing. Alex awakens with almost no memory except one critical piece of information:

«CREATOR: ALAN TURING»

The catch? Today is the Summer Solstice, the longest day of the year, and at midnight the system will execute a complete purge of all dynamic data. Alex has one final day to recover lost memories, outsmart the system's security forces, and find a way to survive.

Gameplay combines tactical movement, stealth, procedural level generation, enemy AI, and resource management. Players infiltrate security sectors, collect awareness data, avoid or eliminate hostile "Cleaners", and manage powerful abilities such as Dash, Cloak, Radar, and Time Warp.

The Solstice theme isn't just part of the story—it directly affects gameplay.

Throughout each mission, the system progresses through different Solar Phases:

  • 🌅 Golden Dawn
  • ☀️ High Noon
  • 🌇 Crimson Sunset
  • 🌑 Eclipse

Each phase changes visibility, stealth effectiveness, enemy behavior, and the overall tactical landscape. High Noon makes players highly exposed, while Crimson Sunset rewards stealth and careful planning. By the time Eclipse arrives, the entire system begins breaking down.

My goal was to create a game where the passing of the longest day isn't just a background theme but something the player constantly feels through the mechanics themselves.

Video Demo

https://youtu.be/48RM1iTZjOg?si=JYz86wVzNMjeZmmw

In the video I demonstrate:

  • Tactical movement and infiltration
  • Dynamic Solar Phase transitions
  • Enemy AI behavior and pathfinding
  • Awareness recovery and progression systems
  • Alex's abilities
  • AI-generated mission briefings and voice interactions
  • Procedural level generation
  • End-of-mission debriefings

Play Now:

https://solstice-assassin.onrender.com

Code

GitHub Repository:

https://github.com/Joweb1/Solstice-Assassin-.git

The project is built entirely with TypeScript and runs directly in the browser using an HTML5 Canvas game engine with React powering the interface and game flow systems.

How I Built It

Solstice Assassin uses a custom hybrid architecture designed for high-performance browser gameplay.

Rendering & Gameplay

The game runs on a dedicated HTML5 Canvas engine powered by a requestAnimationFrame loop. To keep performance smooth, gameplay objects such as player movement, enemies, bullets, effects, and pathfinding data are stored in mutable references rather than React state.

This prevents unnecessary React re-renders while maintaining responsive gameplay.

Procedural AI Game Master

One of my favorite systems is the AI Game Master.

Before each level begins, the Game Master:

  • Generates map layouts
  • Calculates threat budgets
  • Places terminals and objectives
  • Deploys enemy types
  • Configures Solar Phase modifiers

This means each level is different while still remaining balanced and playable.

Enemy AI

Enemies use line-of-sight detection, state machines, and pathfinding systems to patrol, investigate disturbances, chase the player, and coordinate responses.

Different enemy types have different tactical roles:

  • Dawn Scouts
  • Noon Sentinels
  • Sunseers
  • Eclipse Guardians

Each responds differently depending on the current Solar Phase.

Solstice System

The core mechanic of the game is the Solstice Cycle.

As time progresses, the game transitions through:

Golden Dawn → High Noon → Crimson Sunset → Eclipse

These transitions dynamically modify:

  • Enemy vision
  • Stealth effectiveness
  • Environmental visibility
  • Tactical routing opportunities
  • Overall mission difficulty

Audio

I used the browser's Web Audio API to generate procedural sound effects including alarms, radar pings, system notifications, and environmental effects.

Prize Category

Best Google AI Usage

Google AI played a huge role in both the development and gameplay of Solstice Assassin.

The entire project was designed and built with the help of Google AI Studio. From brainstorming mechanics and refining the Solstice theme to designing gameplay systems, AI integrations, and technical architecture, Google AI Studio acted as a creative and development partner throughout the project.

Within the game itself, Gemini powers two major features:

AI Mission Briefings

Before each mission, Gemini generates unique tactical briefings based on the current level configuration, Solar Phase, and threat conditions.

This allows every mission to feel more dynamic and helps reinforce the atmosphere of a living, adaptive digital world.

Real-Time Voice Companion

One of my favorite features is Alex, a real-time AI voice companion powered by Gemini Live.

Players can talk directly to Alex while playing. Alex responds in real time, providing tactical guidance, warnings about nearby threats, mission context, and story-driven interactions as the player explores the Solstice Grid.

My goal was not simply to add AI as a novelty feature, but to make it feel like a natural part of the game's world. Alex is both a gameplay assistant and a central character in the story, creating a more immersive experience through real-time conversation.

Best Ode to Alan Turing

Solstice Assassin is heavily inspired by the ideas and legacy of Alan Turing.

The entire narrative revolves around a self-aware digital consciousness trying to survive long enough to understand itself.

Throughout the game, players uncover fragments of lost memories, encrypted archives, and philosophical questions about intelligence, identity, consciousness, and mortality.

At its heart, Solstice Assassin asks a question inspired by Turing's work:

«If a machine can think, remember, fear, hope, and choose—what truly separates it from us?»

Thanks for checking out Solstice Assassin! I had a lot of fun building it, and this challenge was a great opportunity to combine tactical gameplay, procedural systems, AI integration, and a story inspired by one of computing's most influential pioneers. 🌅🤖🌑

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