This is either way too good or not particularly good at all. Do you get the copies for free? In that case, it's too good. It means that for

, you're copying the spell you play this in response to and then either preventing you opponent from playing any more instants that turn or, if your opponent is dim enough to go on casting instants, you get a whole bunch of additional spells. On the other hand, if you have the opportunity to copy your opponents spells
if you pay their mana cost (not converted mana cost) then this becomes very interesting, but not very good. In any case, you have to specifiy which.
By the way, I know for a fact that Matt has locked three of your threads because you were trying to juggle too many new cards. He lets me do it because I've proven myself capable of managing a lot of cards at once. For the time being, finish up the three other cards you have open and then pursue new cards. You also look like you haven't fully absorbed the forum rules yet. Your initial post should contain the text of the proposed card twice. One instance should be in plain text and should never change. The second instance should be in
bold text and should be updated whenever you make changes to the wording of the card.