the following feedback applies to all 5 icons.
too much blurriness, and there's not much tonal variation (i.e. light & shadow). the way they are drawn, with a lack of shading or depth, makes them look flat, and i'm not sure whether you intended this or not. above all, i think you tried to give it a magical, ethereal, smoke-y/translucent look - and failed. have a look at some reference pictures of smoke/magic beams, and maybe check out some blizzard examples like dispel magic or banish to see where you went wrong.
setting all 5 to substandard right now, but don't be discouraged from making some updates.
see also: sin'dorei300's comments on your 5th icon