the most annoying thing i’ve tried to code is defo procedural generation, especially my Random Map Event Generation 
just because how complicated it was to
- randomly generate something with enough variation to be unique yet consistency so it’s actually playable
- store that data with nested arrays (store map data)
- track player position on the map as an array
- draw the map and player location data to a sprite that works the same way each time it’s opened
and in blocks 
When it comes to extensions like block objects, sprite data and mini menu, what I found useful was to look at the code of existing projects and figure out my own code using that as a template
That can be very difficult for starting right out so tutorials like this: [Tutorial] What are block objects, and how to use them are super helpful. ty @Sarge : D
Finally, scope creep, the death knoll of all my projects lol
How it usually goes is like such:
- make some cool code
- get inspired and massively overplan game to become unreasonably large, complex and difficult to code
- burn out halfway and never finish the game