Godot listening to signals from multiple instances of the same scene

Use a Signal Bus.

Yes, you could iterate over the nodes and find all the enemies (e.g. by comparing their script). However, it is easier if all the enemies register themselves to a list (or a group) on _ready. However, you don’t need any of that.

The insight is this: An object can emit signals of other objects.

We take advantage of that by creating a Signal Bus. Which is a a common pattern in Godot. It goes as follows:

Create an autoload (singleton) script. Let us call it SignalBus.
In the script, define signals. And nothing else. *In our case, we define on_hit:
```
signal on_hit
```
Every place that needs to emit a signal does it from the signal bus. In this case the enemies do this:
```
SignalBus.emit_signal("on_hit")
```

And where you need to handle the signal, connect to it. For example on _ready. Something like this:

func _ready() -> void:
    SignalBus.connect("on_hit", self, "_on_hit")

func _on_hit() -> void:
    # whatever
    pass

This way the emitters and receivers of a signal don’t need to know each other. They only need to know the Signal Bus. Which is available everywhere (by virtue of being an autoload).

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