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I have a question regarding the wording for Shock Longbow +1. The card states:

"For your combat check, reveal this card to roll your Dexterity or Ranged die + 1d8+1; you may additionally discard this card to add your unmodified Strength die with the electricity trait. If you aren't proficient with weapons, the difficulty of this check is increased by 4."

Does that increase by 4 for non-weapon proficiency apply only to discarding the card to add your strength die or does that penalty apply anytime the card is used?

I just stated playing PACG with the Rise of the Runelords base set. This may be a silly question but I can't find a specific example anywhere in the rule books or the FAQ. When playing cards to aid another player's check, can anyone play cards or only other players in the same location where the check is being made? I believe it only makes sense that players in the same location can play cards to assist a check otherwise Harsk's special power is pretty meaningless. Is that correct?