It looks decent, but I think the attack could have been done a lot better. Especially since in the "big reveal" we see like 30 people fall victim to it (I know we're going to see it more, but so far, it's unimpressive). It doesn't have to be flashy and filled with explosions, but it should be impressive and fit the "beauty in simplicity" idiom. This was simple and kind of boring, and not very impressive from a visual stand point. The art for the WN/LN looks much better and closer to the idealbut could be improved as well.
That said, I still think the attack itself, considering the explanations for it, is kinda BS, especially since it's basically "free" and doesn't cost much to use and is pretty much unblockable by magic. I don't like being the "achkasully" guy, but if it were remotely true or sensical, clouds would be floating puffy clumps of doom. I like how it used existing science and got the concept right, but it should have added a more "magical" spin to it to make it more believable and reasonable instead of it being the magic bullet it is. Equivalent exchange and all.