One thing that Diablo does really well is the "make your own game" mechanic.
Diablo players will obviously know this, when you want to go into a game, you create it with your own name, password, etc.
Guildwars should have this put into its mechanic as well. For example, when you go out of town, it's pretty much your own game. There you can set a game name and password, or by default, it is left blank.
This is let people who disconnected rejoin your game or people who want to join you.
Say for example, you have 7 players in your group and you friend wants to join, you can then set a game name/password for them to enter.
Or when someone drops from your game, that person is replaced by a AI until they return.
Don't undersatnd why Anet won't implement this idea.
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