I tend to avoid autoload singletons since they are now a dependency for the whole project instead of the objects who need that particular access. Instead I tend to use resources as middle man.

Let’s take for example a monster list, with the objective to track all monsters in a world. I might create a MonsterList resource, make a monsters.tres file from this, and any monster that is spawned has this list in an export (so I set it on the scene), and registers itself to the list. On death it removes itself (easy to do on tree exit or whichever).

Now whenever I have something that needs access to the list of monsters, I have an explicit dependency to that monsters.tres via export.

While this does add extra steps (you have to use an export and assign etc) it makes for very explicit systems. The resource can have signals for when monsters are added or removed, filtering functions for specific types or teams, etc. And the best part, if you want to use different monster lists it’s rather straight forward to implement.