I bring Silence up because it is commonly seen in World of Darkness, specifically the Slime adds for the Five-Headed Dragon will cast a raid-wide Silence if they aren't killed fast enough, every time it happens and I am on a Healer or a Caster, it's just "Cool, cool, I guess I am not doing anything for the next 10 seconds...", it's not a big deal by any stretch, it's just annoying, and there is very little you can do to prevent it other than targeting the Slimes and hoping enough people also do it.