quick question can u copy a legendary creature I think u can't but I wanted to make sure and I always could be wrong.
You most certainly can copy a legendary. But if you control both copies of it, one must be sacrificed. However if you copy an opponent's legendary creature, you're good to go.
Wait...you and your opponent can have the same legendary creature out?
Yes. The legend rule previously stated that once a player dropped another of the same legendary, they'd all hit the graveyard. But it's been updated somewhere around m14, if I'm not mistaken, to say that each player may control one of the same legendary creature.
It upset some people cuz copying a legendary creature used to be an auto kill.
704.5k (http://imtgapp.com/forum/index.php?action=imtg;area=rule;number=704.5k): If a player controls two or more legendary permanents with the same name, that player chooses one of them, and the rest are put into their owners' graveyards. This is called the "legend rule."