Trigger graphic change effect outside of scenario editor

Hi there AoE fans.
TLDR: Can you script effects to pop up in game from triggers eg(damage to your units) without created a scenario?

I was playing DOTA the other day and it made me want to add a red arrow pointer into AoE when your units get damaged off screen. I can see how I’d possibly do it in the scenario editor. But I haven’t had much luck figuring out a way to do it in normal games.

Is it actually possible to script this kind of change or am I barking up the wrong tree?

You mean like RMS instead of scenarios?

Hi Canine, I mean more like a UI script rather than anything to do with map generation. I want to add it to my overlay, like the small tree’s mod. But this would need to do more than just replace vanilla textures.

I have no idea. Maybe you could try taggin all units as buildings and see if they start burning or something.