What is the ICD file format?
An .icd file associated with Dungeon Keeper 2 is a proprietary binary game resource file from Bullfrog Productions' 1999 Electronic Arts title. These files store game data - graphics, sounds, level information, and text resources - that the game engine loads at runtime.
The internal structure of DK2 .icd files has not been formally documented publicly. Dungeon Keeper 2 shipped with SafeDisc copy protection, and .icd files in that context are also associated with SafeDisc DRM encrypted data, adding an obfuscation layer over the raw resource content. The GOG.com DRM-free release includes compatibility patches that bypass the original SafeDisc protection.
The open-source KeeperFX engine re-implements Dungeon Keeper 1's game logic but does not support DK2 .icd files. No publicly available standalone extraction tool for these resources exists as of 2026.
The .icd extension is shared by several entirely unrelated file types: IronCAD 2D drawing files, Microsoft Windows OpenGL installable client driver files, and Rayman 2 game data. Any tool handling one type will not recognise files from the others. Dungeon Keeper 2 itself remains the only known software capable of consuming its own .icd resource files in their original form.
Security & safety
RISK: LOWStatic binary data file from an installed game; not executable directly. No known exploit vectors.
Format details
in a nutshell- SafeDisc DRM Encrypted Data - ICD files are part of the SafeDisc CD copy-protection scheme used by many Windows games ca. 1999-2007; format marked obsolete.
- IronCAD Drawing - IronCAD 3D CAD software uses .icd for 2D drawing files.
- Microsoft OpenGL Installable Client Driver - Windows OpenGL ICD (.icd) is the driver DLL loaded by the OpenGL subsystem; no end-user interaction.
Programs that open ICD files
Windows2 apps
Dungeon Keeper 2 (game itself)
Paid ICD files are read automatically by the game engine; no manual opening needed. Install from GOG.
KeeperFX (open-source DK engine)
Open-source Community reimplementation of Dungeon Keeper; supports original game data files including DK2 assets to varying degrees. Technical details
deep spec| File type | Proprietary binary game resource/data container |
| Game | Dungeon Keeper 2 (Bullfrog Productions, published by Electronic Arts, 1999) |
| Encoding | Binary, little-endian (Windows x86) |
| Container | Proprietary Bullfrog/EA format; internal structure not publicly documented |
| DRM association | Retail disc linked to SafeDisc copy protection; .icd files carry SafeDisc encrypted data |
| Typical size | Variable - KB to MB range depending on resource type |
| Associated OS | Windows |
| Modern availability | GOG.com DRM-free release includes compatibility patches bypassing SafeDisc |
| Extension conflicts | IronCAD 2D drawings, Windows OpenGL installable client driver files, and Rayman 2 data all share .icd (unrelated formats) |
| Open-source engine | KeeperFX re-implements Dungeon Keeper 1 but does not support DK2 .icd files |
| Developer | Bullfrog Productions (development); Electronic Arts (publisher) |
| Community tools | No publicly available extraction tool for DK2 .icd resources as of 2026 |
| Public specification | No format specification or SDK released publicly by Bullfrog Productions or Electronic Arts |
| Released | 1999 (Dungeon Keeper 2 release) |
| Latest version | N/A (static game format) |
Community Q&A
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