auras don't work on mercenary

The purity of the elements has no effect on the mercenary. He doesn't get resistance, he doesn't get immunity to ailments, and he doesn't have a circle around him to indicate that he is affected by the aura.
Other auras don't seem to work on mercenaries either. However, items such as Leer Cast, which have similar descriptions to the auras, do work

So it seems that it's my character is bugged or it's happening because he's still in campaign, as I've tried it on other char who's in maps and everything is fine. Same merc, same location.
I don't know what to think at this point

ok, I'm just dumb. I have gloves that makes so that auras works only on linked targets. I can't read apparently