Playing an instant defeat when there's a Mate.
 

"Mate." A monster is in play and someone else plays Mate on it to create a similarly powered copy. Then lets say the player in combat has some sort of item that lets them instantly defeat a monster. They can choose which monster to defeat. If they choose the original is the Mate monster also defeated cuz it was a copy and theres no monster to copy anymore?
I wonder because I've read if you "Illusion" the original into a different monster the "Mate" copy also changes.

Re: Playing an instant defeat when there's a Mate.
 

The Mate is a copy, but it represents an individual Monster. So, removing the original won't remove the Mate. That's why we suggest just removing the Mate in those instances, since it will be much easier. Our reasoning is that the Mate will remain and still have the same combat strength it did before the original was removed, so why make life difficult?