Plague spell

Plague spell

Hi I need a plague spell done for my map.

Ill give you a rundown on what i want

This spell is going to be thrown by a hero of some sort.

The disease cloud when this is thrown can be seen but infected units cannot be seen.

Infected units can pass on the disease through touching.

When the unit dies a cloud bursts from him realsing a zombie with a visible plague cloud, Which can infect units.

This rapdily declines health.

This may or may not be difficult to do, i dont know since i never worked with making an ability this complicated or triggers.

Thank you if anyone can help

First: Do you know it's against the rules to spam? It would be wise if you delete your other posts before someone comes here, looking for people to ban.

Second: I think I can make your spell, but I may need some extra info. PM me if you want me to make this spell.