Diplomacy is Not an Option - Technical Game Notes

Last Updated: 2026-03-09 Status: Research complete (initial pass)

---

Game Overview

• Genre: Medieval siege defense RTS / city-builder
• Developer: Door 407 (door407.com)
• Engine: Unity with full ECS (DOTS) architecture
• Scripting Backend: Mono (NOT IL2CPP)
• Platform: Steam (PC / Windows)
• Release: February 9, 2022 (Early Access), October 4, 2024 (Full Release)

---

Modding Landscape

Official Support

• Map Editor (added May 2025) with full Steam Workshop integration
  • Adjustable terrain, enemy horde waves, timing
  • Mission objectives (defend/attack, survive/prosper)
  • Random or manual landscape options
  • Resource difficulty settings
• December 2025: Winter update making Undead faction playable in Map Editor
• No official overhaul/mod SDK
• No official API documentation
• Developer stance: "open to community mods but prioritize core game development"

Community Modding

• Small Nexus Mods community
• BepInEx-based modding via modified BepInEx 5 with Doorstop pre-loader fork
• Standard BepInEx from GitHub DOES NOT WORK - requires specialized ECS build
• Custom BepInEx/ecs_plugins/ install path (differs from standard BepInEx)
• Nexus/Vortex support confirmed (Vortex extension auto-installs BepInEx)

Existing Mods (Nexus)

1. BepInEx 5 with Unity ECS Support - Foundation loader
2. Resource Fairy - Configurable resource/storage multipliers (F1 ConfigManager)
3. Trainer and Multipliers - Unit damage/speed/health, building health, population multipliers

Existing Code Repos

• devopsdinosaur/dno-mods (GitHub) - Primary mod source repo
  • Visual Studio solution (dno-mods.sln)
  • Directories: resource_fairy/, shared/, system_test/, testing/, third-party/
  • 100% C#, 29 commits, single contributor
  • All built mods published on Nexus

---

Key Technical Details

ECS Architecture

• Uses full Unity ECS (Entity Component System) via DOTS
• Not hybrid ECS - full DOTS implementation
• Burst compilation for performance
• Custom ecs_plugins flow for game-specific plugins

BepInEx Setup (CRITICAL)

• Standard BepInEx from GitHub does NOT work
• Required: BepInEx 5 with modified Doorstop pre-loader (C++ winhttp.dll)
• Doorstop fork allows multiple assembly pre-loading
• Source: Nexus Mods (diplomacyisnotanoption/mods/1)

Folder Structure:

GameRoot/
  winhttp.dll              # Modified Doorstop
  doorstop_config.ini
  BepInEx/
    plugins/               # Standard plugins folder (EMPTY for DINO)
    ecs_plugins/            # WHERE DINO MODS GO
    config/                 # Configuration files

Modding Path

1. Install modified BepInEx/Doorstop for Unity ECS
2. Mods go into BepInEx/ecs_plugins/, NOT standard BepInEx/plugins/
3. ECS-native mods preferred over Harmony patches
4. Plugins use attribute-based registration (standard BepInEx pattern)

Harmony Compatibility

• Prefix patches (run before methods): COMPATIBLE
• Postfix patches (run after methods): COMPATIBLE
• Transpiler patches: NOT RECOMMENDED (ECS architecture limitations)
• Performance Warning: Steam guide (id:3348001330) warns severe perf cost
• Removing Burst-generated DLL can halve frame rate
• Recommends writing ECS-based mods directly

---

Key Game Systems

Economy

• 5 resource types: Food, Wood, Stone, Iron, Gold
• Trading system via "merchant dirigible"
• Gold obtained exclusively through trading (high exchange rates)
• Resource production and storage critical to strategy
• Late-game heavily dependent on gold conversion strategy

Military

• Real-time combat with pause mechanics
• Unit positioning and flanking critical
• Diverse unit types (cavalry, infantry, archers, etc.)
• Progressive unit unlock via tech tree
• Unit upgrades through research

Building

• Economic buildings (farms, woodcutters, quarries, mines)
• Military buildings (barracks, stables, towers)
• Production buildings (markets, smithies)
• Research buildings (universities)
• Defense structures (walls, gates)

Technology & Upgrades

• University reduces research time
• 14+ technologies available
• Tech tree system with dependencies
• Unit and building upgrades

Magic System

• Magical monuments
• Soul crystal harvesting
• Summoned units/ghosts
• Beam attack spells

Waves & AI

• Procedurally generated maps with enemy spawns
• Wave-based enemy assault system
• Multiple attack directions
• Progressive difficulty scaling
• "Vast hordes" (25,000+ enemies reported)

---

Vanilla Unit-to-Role Mapping (for mod conversion)

These vanilla game elements map to abstract modding roles:

Vanilla Element	Abstract Role
Peasant worker	Economy worker
Swordsman	Line infantry
Archer / ranged	Ranged infantry
Cavalry	Fast strike unit
Catapult / trebuchet	Siege / artillery
Walls / towers	Static defense
Farms	Economy primary
Town hall / castle	Command center
Magic / soul	Special ability proxy

---

Tool Chain

Tool	Purpose
BepInEx 5 (ECS build)	Plugin/mod framework (modified for DINO)
HarmonyX	Method patching (use sparingly - perf cost)
AssetRipper	Unity asset extraction
dnSpy / ILSpy	Managed assembly inspection / decompilation
Unity.Entities	ECS-native system creation
Visual Studio	Mod development (C#)
ConfigurationManager	In-game config UI (F1 key)
Vortex	Mod manager with DINO extension

---

Open Questions

• [ ] Exact Unity version used by DINO
• [x] Mono vs IL2CPP runtime -> Mono confirmed
• [ ] Complete entity/component namespace map (requires decompilation)
• [ ] Prefab organization and naming conventions
• [ ] Asset bundle structure
• [ ] Localization table format
• [ ] Research tree data format
• [ ] Wave composition data format
• [ ] Available hook/patch points in ECS systems

---

References

Primary

• Nexus Mods - Diplomacy is Not an Option -- Mod downloads and community hub
• BepInEx 5 with Unity ECS Support -- Required mod loader (modified Doorstop fork)
• Steam Community Modding Guide -- "Modding is an Option (with BepInEx)" -- primary BepInEx setup reference
• devopsdinosaur/dno-mods -- Community mod source code (Resource Fairy, Trainer)
• Steam Workshop -- Official map sharing (Map Editor maps only, not code mods)

Nexus Mods Available

• BepInEx 5 with Unity ECS Support -- Foundation loader
• Resource Fairy -- Configurable resource/storage multipliers (F1 ConfigManager)
• Trainer and Multipliers -- Unit damage/speed/health, building health, population multipliers

Secondary

• Vortex Extension for DINO -- Adds DINO support to Vortex Mod Manager (auto-installs BepInEx)
• PCGamingWiki
• Fandom Wiki
• ModDB
• SteamDB Patch Notes
• Door 407 (Developer)
• Steam Store Page

Map Editor (Official)

The May 2025 update added a full Map Editor with Steam Workshop integration:

• Adjustable terrain, enemy horde waves, timing
• Mission objectives (defend/attack, survive/prosper)
• Random or manual landscape options
• Resource difficulty settings
• December 2025 update made Undead faction playable in Map Editor
• Maps only -- the Workshop does not support code mods

Comparable BepInEx Modding Scenes (for reference)

• Valheim (mature BepInEx + Thunderstore ecosystem)
• Risk of Rain 2 (BepInEx reference game)
• The Long Dark (Harmony patching reference)
• RimWorld (modding-friendly architecture reference)