Introduction

This website serves as a reference for Custom Difficulty 2, a mod for Deep Rock Galactic which allows the creation of new hazards, or difficulties. Developed by @TheBrain as a successor to the Custom Difficulty mod, CD2 features many improvements over the and possibilities offered to difficulty designers:

Allows players to a have a much finer control over many aspects of the gameplay by introducing mutators, control flow structures similar to those found in common programming languages.
Exposes many enemy controls to change their behaviour, spawning mechanics and even aspect by featuring custom materials replication to clients.
Allows manipulating the enemy pools live during a mission based on gameplay conditions.
Offers many features not available in CD1 such as controls for illumination, player scale, the amount of nitra in the map, etc.
... and many others.

Main Sections

Basics. The basics of CD2.
Modules. A list of the top level modules for a valid CD2 file.
Enemies. Reference for the Enemies or EnemiesNoSync modules.
Direct. A compilation of Direct enemy controls with default values.
Wave Spawners. Reference for the WaveSpawners module.
Projectiles. Reference for the Projectile field of enemy descriptors.
Mutators. A list of currently supported mutators.
MEV, DEA and EEE. A reference for the MEV and DEA mods and links to the EEE reference, used to add new enemy variants into the game.
Common Edits. Reference section for common difficulty edits.
Resources. Useful links related to Custom Difficulty.

Update Log

4-Dec-2024: Updated for CD2-v9: added ByEscortPhase and ByRefineryPhase mutators.
25-Dec-2024: Updated for CD2-v10: added the Projectiles page, added the MEV and DEA page, added an explanation for elite and veteran enemies in Enemies, added the explanation for the new Spawner enemy control, and some minor corrections.
29-Jan-2025: Updated for CD2-v11: added the Direct and UsesBiomeVariants enemy controls and the BySaboPhase mutator.
20-Feb-2025: Partial update for CD2-v12: added the DefenseProgress and ByResuppliesCalled mutators, added the Salvage module and the BySalvagePhase mutator.
28-Feb-2025: Added @Carrot's projectile resource to the Resources and Projectiles tabs, added @Spy's guide to pubbing with CD2 to Resources and to the FAQ, added EEE's reference to Projectiles and to MEV, DEA and EEE.
11-Mar-2025: Update for CD2-v13: added the legacy pawn stats to enemy controls, added BySecondary and DwarfCount mutators, added Darkness module descriptions, added Salvage.Minimules.NitraToGive to the Salvage module
22-Mar-2025: Update for CD2-v14: added the Dense Biozone option to the ByBiome mutator, added descriptions to Movement enemy module provided by @emctwo.
25-May-2025: Update for CD2-v15: added the Diversity option to the wavespawner section, added the new Trigger mutators to the mutators section, added the Heal advanced controls and the new Outline control to enemies.
2-Jun-2025: Clarified the section about the differences between Enemies and EnemiesNoSync in Enemies; removed the DEA enemy list from MEV, DEA and EEE and added a link to the mod in mod.io and to the official list.
23-Jul-2025: Added the Direct page.
15-Aug-2025: Added the Usable table in the Salvage module in Modules and some examples.
11-Nov-2025: Update for CD2-v16: added the Countdown, EnemiesRecentlySpawned, Int2String, Float2String and the Join mutators; added the Messages and SoundCues module; added the FallDamageStartVelocity and FallDamageModifier in the Dwarves module.
2-Dec-2025: Update for CD2-v17: added the Vars module, the Alert field on wavespawners, the DroppodDistance, MuleDroppodDistance, Nonzero, Select, EnemyHealth, EnemyDistance, SecondaryFinished, LockFLoat, LockBoolean and LockString mutators.
11-Dec-2025: Added the Common Edits section, changed theme to material.
8-Mar-2026: Update for CD2-v18: added the StopWatch, TriggerTimer, Sequence and SelectFromArray mutators, added the Goomba and DropResources enemy controls to Enemies.