Plague Inc: Evolved

Plague Inc: Evolved

Immune Systems Challenge
Custom Scenario Help
I was wondering how to make a scenario where an event triggers an event saying people are attacking a random country and slowly kill it, and for the players to stop it they need to evolve an ability I put in the thing or infect the entire country and if the world has a certain amount of people killed in percentage that the player loses, kind of like this scenarios recovered people, pls help, possibly indigofenix can help?