Pls help with custom spell

Here's a spell I want to implement but I can't figure out how to. It's called Fire Storm. The spell functions like starfall except that the hero can walk around and attack while it is active.

In the RoC DOTA maps there's a spell for the Sidereal Engine called Astro Protection which is how I envision it working. Unfortunately the map is protected so I can't butcher it and find out how it works. I do know that it creates an invisible unit to follow u around creating the falling stars, and I have already implemented the dummy unit but I dunno what to tell it to do.

Help please!

Also, anyone know if it's possible to do a slow aura without importing .txt & .slks (as this would screw up the spells I've already done)? I know it can be done with a mod of the tornado aura, but this doesn't have an icon to let u know u have it.

Thanks, but I don't think this will work as planned because the guarding unit will not attack randomly. It will just drop fireballs on one unit until it dies, which'll look pretty strange.

I'll try that, thanks!

If you have TFT it is simple:

You only have to make a custom aura based off endurance (or any aura that changes movementrate). You can make this aura in the Object-Editor without messing around with .slk or .txt files.

Then go to Preferences and there under the General Tab chose to allow negative Real-Values.

Now you can change the Movementratebonus of your custom aura to a negative value and thats it.