Cannot be cancelled plot cards

By Daenarys, in 2. AGoT Rules Discussion

Scenario :

Middle of a battle with multiple charcters out for each side with duplicates on characters

A plot card is played that destroys all but 3 characters. Does this INCLUDE all duplicates. Put another way if i had 5 characters ut and each character had 2 duplicates attached would i have to destroy two characters and their subsequent duplicates ?

I hope this makes sense

Thanks