Guild Wars 2

So I’ve been enjoying stealing boons, but for the life of me it looked like I could not steal any of the effigies might in CoFP1. Does this not work against certain opponents? Perhaps those with defiant?

Sorry for an obscure and noobish question. Just wondering if what I was seeing made any sense.

Edit: I don’t normally play thief at all, so forgive me if I don’t know something obvious.

Those aren’t ordinary boons – they are set bonuses that use the boon icon or something similiar, and thus can’t be removed by normal means. You know a boon is available to steal or remove when it has a duration attached (the white outline that ticks down). Compare the effigy’s buffs to, for example, the Butcher in HotW P1. You can steal his boons every time they refresh without a problem.

Thank you, Auesis for that clear response!