My playgroup occasionally plays a semi-pauper EDH (Allowed 5 rares / mythic rares including your general) one of my rares is, obviously crucible of the worlds. This card can work particularly well, if for nothing else than the fact it's repeatable and can deal with an entire type of card, also in EDH eventually you'll end up hitting a point where your land is just getting out of control and fills up half the table. I like to be able to clear it up occasionally. In the format I use it in, it's easily a 4/5 but in other formats the most I can see giving this is really a 2.5/5, in most instances a disenchant would be more usable. Will give it a 3/5 overall.