Scripting / Coding

[Pandemoneus]

Well, it helps pretty much when you actually programmed using a programming lanuage a bit already. I never read through the angelscript manual, as it looks pretty much like C++ (which I already knew a bit).
In case you never scripted before, you might actually load the developers' script files in a text editor and look how they've done it. They can be found in maps/main/ch01 and so on, the file extention is .hps
If you already completed the game you might see what effects different parts of the code had - if you can remember what happened in the different maps that is.

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There is also a little scripting tutorial in the wiki, check it out if you didn't do already.