Explain to me how no one can say the word 'Battletech' after seeing that picture?

First thing through my head was 'I didn't know they were reusing art from Battletech in Magic!' I'm telling you guys, that is SO Mechwarrior 3.
Oh, yeah, there's text on it... Personally, I like this card. I probably won't play it much (directed removal is not my favorite, I perfer massive sweeps), but it's very powerful. Unfortunately, it's also very situational. I can't see that card being very good in multiplayer, either. Powder Keg tends to frighten people and make them come after you, but Void is a threat you don't play down; people will be scared of it even if you don't have it! That's Bad(tm).
In duels, I can see it functioning nicely. What you have is an overcosted removal card with a sometimes worthwhile discard effect thrown in for good measure. The plus side is, you can leave your creature intact while wiping out several of your opponent's, and end the game in a mad rush to victory. There's the problem of the restricting casting cost, but the sheer power of it as a removal spell makes it powerful.
Put simply, though, I would look forward more to Recoil or Lobotomy than this. But the art makes it all good.