Well, it all depends if you want to make a new character or not.Originally Posted by Rodenty
If your wanting to continue with a previous character that has heroes, you will need at least Nightfall or Nightfall in your GW collection (little more than just that). If you plan on making a new character, you do not need Nightfall.
You can use any of the 3 campaigns to play GW:EN since the catacombs span the whole world of Guild Wars. The catacombs in Prophecies is just a portion of the catacombs that spans the world of Guild Wars. Since the story of GW:EN involves the exspansive underground known as the catacombs, it involves all the campaigns. In most part, its a continuation of Prophecies.
GW:EN has the features of all the campaigns. So you can create a new character in GW:EN, but you will only have access to the heroes of GW:EN.
If you have Nightfall as your core game or part of your collection, you can use both GW:EN heroes or Nightfall heroes (if you travel to obtain the heroes from the other campaigns to Nightfall).
