hopkeepers inside the city of Portal are protected by the laws of the city's Lord. As the gods have pledged their favor to the city of Portal, they have imbued these shopkeepers with the powers necessary to carry out retribution against those who defy these laws. In short, anyone who chooses to attack a Portal shopkeeper will die brutally. In addition, they may find themselves facing the direct wrath of the gods in hell...

A Portal shopkeeper is any mob inside the city of Portal at which you can type 'list'. If you are given a list of items for sale, or are told to try back later, it is a shopkeeper. This also applies to guild shopkeepers and the blacksmith.