Name that Skill.

I came up against a skill today in GvG, that I made sure to unlock, but iv gone and forgotton its name, AND I cant seem to find it anywhere in priest of Balthazaar.

So can anyone help me out and 'name that skill'?

HEX "For XXX seconds target foe cannot be the receiver of any enchantments."

I am not sure if that the exact wording, I cannot tell you for sure which class uses it (I thought mesmer but cant find).

I had Inspired Hex, so stealing this was a whole lot of fun, and I desperatly want to unlock it, if only I could find it.

Shadow Shroud, an assassin elite.

Thats the one, Assassin elite.

Makes sense why its not in the mesmer skill list.

Thanks for your help dude.