Sending info about spawned actors to Level Blueprint

This question is very similar to this one about spawned actors reporting their death, and while that answer was very helpful and illuminating for me, I’m still struggling to get some traction on a problem I’m having.

I cannot figure out how to send data about spawned actors back up to the level blueprint. The example I’m doing is a simple asteroids clone, and every time an actor dies it spawns multiple offshoot actors, and those offshoot ones also spawn children, etc. I have all the logic and gameplay working in the Blueprint of the asteroid actors to track their deaths, send it to the HUD for a running score, spawn new guys where they died, etc. But what I can’t do is pass any information about them back up to the Level Blueprint. The most simple thing I want is to keep a running count of how many are alive at any given time with a running int variable that I can then use to dictate further behavior inside the Level Blueprint. Maybe something like, if more than 10 asteroids, play faster music or something. That’s just a random example, the real problem is I can’t figure out how to get the pieces talking to each other. I’ve been researching every link I can find, and I usually have trouble because the solutions working with actors placed in a level (not spawned) or sending info to blueprints other than the Level Blueprint (like the HUD, or GameState).

As far as I know, the level blueprint doesn’t even have a named type (though I could be wrong), so it would be next to impossible to send anything to it. It can catch events, and it can ask actors for their whereabouts, but actors accessing the level BP looks unlikely. Anyhow, what you’re trying to achieve is more than easily achieved by passing all this data to your GameMode and doing all your logic in there. That’s what it was meant to do in the first place. Besides, the “level” BP is meant only for “level” specific behavior. You know you’re going in the wrong direction when you open a new map and find the need to copy another map’s blueprint into this one’s.

Interesting. At first I was going to say that seems slightly at odds with most of the sample content, but when I looked closer, yeah, I can see that. The level blueprints seem to be for setting up the camera and player, and that’s about it? The only exception seems to be the Tower Defense sample project… I wonder why that one is different? Is there any documentation that outlines the “best uses” for each kind of blueprint?