Board Thread:Off Topic/@comment-25396609-20160207042716/@comment-26397825-20160229073827

And the reason why Adam's semblance 'cut through' Yangs aura is actually that his attack was so powerful it completely depleted Yang's aura and then continued on. This was rveealed to us in the RWBY Afterbuzz Ep 11-12 video, around the 50 minute mark, said by Miles himself.

So it's not that the semblance is OP, but rather that Adam was too strong, and Yang wasn't on full aura as she had been fighting Grimm and stuff during the invasion.