Legacy GM Question about Undertale's Source Code

[Evan Kinsler]

So one way I am trying to study GameMaker Language is by observing the codes as carefully as I can. If that even is a valid method of learning how to learn GML.

I have recently been doing some research with Undertale's demo source code and since practically every single demo I'm directed to--because some demos are on GitHub, others lead me to a dropbox website and others lead me to https://undertale.com/demo/ . However despite all of these different versions of the Undertale demo, they all have the exact same scripts, objects, sprites, sounds and so on.

I'm just curious about how you would go about creating your own rooms, writing your own dialogue, developing your own cutscenes, programming your own fights and triggering certain endings. Which scripts and lines of code would be used to essentially make your own adaptation of Undertale.

To have a better way to visualize what I have in mind, please play this fangame. It sums up the graphics I'm visualizing pretty damn well: https://gamejolt.com/games/horrortale_the_game/289657

Where would I go or what kind of codes would I have to observe in order do the things featured in a fangame like this one?

 

[SoVes]

What I think you should do is start the project. And when you can't resolve a problem, google it. It gets very overwhelming when looking at big project files. There are plenty of great tutorials for many things and here are multiple ways of approaching things, but that's how I'd approach it.