Mass Battle Resurrection.

First thing first, this is pretty minor. It's basically like a second Mass Res.

You're wiping, everyone has Mass Res debuff. This would come in handy somewhat in a situation like that.

If a Battle Res is available a Death Knight with the "Glyph of Raise Ally" can cast Battle Rez on everyone who is dead until someone accepts it. If you Battle Rez everyone who is dead while wiping they all can accept it after the wipe.

Like I said, it's not huge, but hey, is what it is.