The new Marvel VS expansion introduces The Defenders and The Underworld teams!
The characters in VS System 2PCG: The Defenders can have different versions on each team. For example: Daredevil and Dr. Strange can be Defenders as well as Avengers. Note: the characters team affiliation does not affect "Powering Up".
Plot twists can be played at a choice number of times - just follow the appropriate text. When it comes to Protection - your face-up front row characters protect your face-up back row characters. Some effects say to "wound" a character - which starts a wound counter on the character. However, this does not stun a character.