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The default command launches the full game flow with menus, gameplay modes, and UI.

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Usage

crimson [OPTIONS]

# Explicit run (same as above)
crimson run [OPTIONS]

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Options

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--width
int
Window width in pixels.Default: Use value from crimson.cfg
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--height
int
Window height in pixels.Default: Use value from crimson.cfg
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--fps
int
default:"60"
Target frame rate.
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--seed
int
RNG seed for deterministic runs.When set, all random events (spawns, perks, drops) will be reproducible.
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--demo
flag
Enable shareware demo mode.Restricts available content to match the original 2003 demo version.
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--no-intro
flag
Skip company splashes and intro music.Useful for rapid iteration during development.
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--debug
flag
Enable debug cheats and overlays.Provides access to:
  • Frame time overlays
  • Entity debug info
  • Cheat commands
  • Developer UI
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--rtx
flag
Enable non-canonical RTX render mode.
This is an experimental enhanced rendering mode that deviates from behavioral parity with the original game.
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--preserve-bugs
flag
Preserve known original executable bugs and quirks.For maximum parity testing. Enables original game bugs that have been documented.
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--base-dir
Path
Base path for runtime files (saves, config, logs, replays).Default: Per-user OS data directoryOverride with CRIMSON_RUNTIME_DIR environment variable.
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--runtime-dir
Path
Alias for --base-dir.
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--assets-dir
Path
Assets root directory.Default: base-dirMissing .paq files are automatically downloaded.

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Examples

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Basic Launch

# Use default settings from crimson.cfg
crimson

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Custom Resolution

crimson --width 1920 --height 1080

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Deterministic Seeded Run

# Same seed always produces identical gameplay
crimson --seed 42 --no-intro

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Shareware Demo Mode

crimson --demo

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Development Mode

# Debug overlays, skip intro
crimson --debug --no-intro

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Custom Runtime Directory

# Keep all files local to project
export CRIMSON_RUNTIME_DIR="$PWD/artifacts/runtime"
crimson

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Point to Original Game Assets

crimson --assets-dir /path/to/crimsonland_classic

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High Frame Rate

crimson --fps 144 --width 2560 --height 1440

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Preserve Original Bugs

# For parity testing against original exe
crimson --preserve-bugs --seed 12345

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Runtime Files

The game creates the following structure under base-dir: 
base-dir/
├── crimson.cfg          # Configuration file
├── saves/               # Save games
├── replays/             # Recorded demos (.crd)
├── logs/                # Game logs
└── screenshots/         # Screenshots (F12)

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Configuration File

The game reads settings from crimson.cfg in the runtime directory:
  • Screen resolution
  • Windowed/fullscreen mode
  • Texture scaling
  • Audio settings
Use the config command to inspect values.

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Game Modes

All original game modes are available:
  • Survival — Endless waves of enemies
  • Rush — Race against the clock
  • Quests — 5 tiers of campaign missions
  • Tutorial — Learn the basics
  • Typ-o-Shooter — Type to shoot

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Keyboard Controls

See in-game tutorial for full controls. Common keys:
  • WASD / Arrow keys — Movement
  • Mouse — Aim and shoot
  • 1-9 — Weapon hotkeys
  • F12 — Screenshot
  • ESC — Menu

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Deterministic Simulation

When using --seed, the entire game simulation is deterministic:
  1. Enemy spawns occur at identical times and positions
  2. RNG rolls for perks, drops, and damage follow the same sequence
  3. Float32 math behavior matches the original executable
  4. Replays can be verified bit-for-bit
This enables:
  • Reproducible bug reports
  • Replay verification
  • Parity testing against original game

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See Also

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