Board Thread:Speculation House/@comment-27404492-20170511131216/@comment-25936766-20170516045640

SpiritedDreaming wrote:

....However, it was easily disrupted by Amber destroying the other Emerald she was seeing, which implies that if you destroy the illusion, you break the hold Emerald has over your mind. Nah, I'm 100% sure that when Amber destroyed Faux Emerald, the real Emerald was just surprised for a moment - which broke her concentration, meaning the Ilusion in itself (or Antillusion? What's the term for not sensing things that are there?) vanished.

Which points out the biggest weakness in her Semblance: She needs to concentrate. So if something breaks her concentration, she loses that advantage even if momentarily.