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Crimsonland Hero Light

Welcome to Crimsonland

Crimsonland is a high-fidelity reimplementation of Crimsonland v1.9.93 (2003, GOG “Crimsonland Classic”) in Python + raylib, paired with deep reverse engineering of the original Windows binary. The aim of the project is behavioral parity: timings, RNG sequences, float32 math, UI layout quirks, asset decoding, and gameplay rules match the original as closely as practical.

Current state

The rewrite is a playable full game: boot, menus, Survival, Rush, Quests (5 tiers), Tutorial, and Typ-o-Shooter, with full weapon/creature/perk content, terrain/sprite/decal rendering, music, gameplay SFX, and even secrets. The simulation is fully deterministic, supporting seeded runs and headless verifiable replays.

Key features

Behavioral parity

Timings, RNG sequences, float32 math, and gameplay rules match the original

Deterministic simulation

Supports seeded runs and headless verifiable replays

Full game modes

Survival, Rush, Quests (5 tiers), Tutorial, and Typ-o-Shooter

Differential testing

Headless testing harness verifies runs against the original game

Get started

Quickstart

Get up and running in under a minute with uvx

System requirements

Check if your system meets the requirements

Install from PyPI

Install using uvx or pip for the latest stable release

Install from source

Clone and run from source for development

Tech stack

Python 3.13+ · raylib (pyray) · Construct · msgspec · Typer · Ghidra · Frida · WinDbg · pytest · uv This project is an independent reverse engineering and reimplementation effort for preservation, research, and compatibility. No original assets or binaries are included. Use your own legally obtained copy.

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