I’ve always loved CI5, and like many of you, I’ve spent countless hours playing it. A while ago I got the idea to build something that really replicates the game – not just a quick clone, but a proper engine that captures its physics, enemy behaviour, weapons, and waves.
The goal was to make it open‑source so anyone can learn from it, mod it, or even build their own game on top of it. I wanted it to be as faithful as possible to the original while keeping the code clean and well‑structured.
What’s inside the ZIP?
A complete folder structure (Engine/Core/, Engine/Entities/, Engine/Levels/, Engine/Network/).
31 .h and .cpp files – together about 2500+ lines of code.
Full simulation of:
• All 13 weapons with their unique stats and upgrade levels.
• 10+ enemy types (chicken, chick, UFO, armoured, toxic, chiller, phoenix, coward, space, pilot, boss) each with their own behaviour.
• The 120‑wave system (12 chapters × 10 waves) and multi‑phase boss fights.
• Physics (powered by Box2D) that mimics the original UVE engine.
• Power‑ups, keys, bombs, shields, and invincibility.
• Multiplayer support (via NetworkManager – ready to be extended).
Everything is written in C++20 and uses SFML for graphics/audio and Box2D for physics
How to build and run it
Download the archive from the link below.
Extract it – you’ll get a folder named CI5_Ultimate.
Important: The engine only contains the source code. You need to provide the actual assets (.tga sprites, .ogg sounds, .lev level files) yourself. Place them inside the Assets/ folder as described in the code.
Open a terminal inside the CI5_Ultimate folder and run this command (make sure you have g++ and the required libraries installed):
g++ -o CI5_Engine.exe main.cpp Engine/Core/.cpp Engine/Entities/.cpp Engine/Levels/.cpp Engine/Network/.cpp -lsfml-graphics -lsfml-window -lsfml-system -lsfml-audio -lsfml-network -lBox2D -std=c++17
If everything compiles, you’ll get a CI5_Engine.exe – run it and enjoy!
What’s missing / what you can add
The engine is complete logic‑wise, but you still need to bring your own graphics, sounds, and level files to make it a full game.
I’ve kept the code modular on purpose – you can easily tweak weapon stats, add new enemy types, or even create entirely new chapters
I’d love your feedback and contributions!
This is just a starting point. If you have ideas, want to fix a bug, improve the physics, or add a feature, feel free to jump in. Ask questions, report issues – let’s make this something cool together
Download link: CI5_Ultimate
Thanks to everyone who encouraged me along the way. Hope you enjoy it!
I will delete my account, @everyone. Please, I will delete my account because you didn’t appreciate it. And thank you, developer, for hurting someone who respects and appreciates you. And thank you to everyone. I spent hours working, and in the end, there was no interaction and I was bullied. I don’t deserve this forum because I was an active person and I loved you all from the bottom of my heart. Thank you anyway because this forum is not for me, and I will not allow my dignity to be insulted. I will return in 24 hours and I will delete my account.
At least you made this decision all voluntarily. No one have to say it out loud.
Huh?
The fact that you begged interactions from others on a website that you spent 6 months to made without realizing the limitations of localStorage already tell it all. Even a beginner would really avoid this.
And no, those are not an unjustified bully at all. Those are coming from the fact you’re hiding behind the AI.
It’d be better if you didn’t overuse AI to the point you prompted it to even make a respond for you. Denying the usage of it won’t work.
We, the forum users, aren’t the dumb headless chickens like you thought. What looks like AI, what the code does, who made it, who wrote it, we all knows by just looking at the first glance.
Okay, I respect you, but don’t accuse others. I did get some light help from it, but in my opinion, I don’t like dealing with any artificial intelligence because it doesn’t give you accurate information, and that’s why I don’t use it much. I write and edit everything myself. I’m a developer like you and some other people. Everyone uses AI without justification, and that’s for assistance. Also, it only helps me with the language. I don’t want to use it. You’re just making a big deal out of it. How can you accuse someone of doing 100% AI work? Check out my other posts; you’ll find some that are 100% AI-powered by other people. But you deserve respect, and respect is due to everyone. Respect others so that others will respect you. Suggest solutions; don’t tell me to stop. I don’t like AI; I only like it for assistance with development, and I mean for organization, not because I rely on it to write the code and organize everything for me. I write the code, and it organizes the ideas. I’m sorry. This is my message to everyone. Have you used AI? My artificial arrangement of ideas for the iamt work rate is not a flaw; I admit it because I reviewed it. It’s not shameful for a person to admit their mistake.
