Yes you will need Python. You can't create event in Python only - they must be created through XML. However, the XML system isn't very flexible, so you need Python for something more complicated. In this case, damaging units, subtracting a random amount of pop and creating fallout would all require Python.
I like this form of the event you're proposing here, and it's not difficult to create. If you want to learn about modding events, check the link in my signature, I have a huge guide on the subject.
I like this form of the event you're proposing here, and it's not difficult to create. If you want to learn about modding events, check the link in my signature, I have a huge guide on the subject.