In the late modern age, around eight of my automated workers headed toward Babylon, one of my most productive cities. As they attempted to enter the city, they were attacked by the MI stationed inside. All eight of them were killed.(my MI became elite too, lol

)
I remember reading about this a while ago, and I was not so much angry as interested and amused by seeing this happen to me.(It was Modern age, eight workers didnt matter that much to me.)
So I laugh and go bak to the game. A few turns later, I attempt to move a MI from one of my core cities to a border city. The same thing happened as before, except this time with MI!
Imagine if this happened with a large stack of your units and another stack of your units