Hello,

If I play house of dream and then I play Den of the wolves, considering both effect are passive and permanent qhat is prioritary? den or HoD, in other words does my location become vulnerable or does it stay immune ?

it stays immune. it is immune to non plot card effects and you are trying to remove it's immunity with a non-plot card effect.

No, it is immune to opponent's non-plot card effects, not yours. Your cards can still hurt your HoD Location: for ex, if you play a Newly Made Lord and there are no non-Limited Locations in play other than your HoD Location then you screwed up big time.

A moot point though, since Den only removes immunities from Characters and not from Locations.

right, my mistake