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There's no official DLL to assemble against or open source project but if you want to dig around in the source code you can use https://www.jetbrains.com/decompiler/ or some other tool: http://stackoverflow.com/questions/2646707/something-better-than-net-reflector on Caves of Qud\CoQ_Data\Managed\Assembly-CSharp.dll

The XRL.World.Parts namespace contains all the part definitions in the game, so it's a good place to start digging.

Detailed Scripting Topics

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