Yes you *only* need to do the mission specified in the achievement if you've already done them on that character. No need to do them in order by active mission. I took a chance on it myself yesterday because I got bored with the talking and talking and taaaaaaaaaalking. You can skip a fair bit of story. Start by doing Story mode to get a feel for the dungeon. Check here to see which ones you can do at your current level. Don't be afraid to mention that it's your first time. GW2 is famous for having a great community of players and 90% of the people you meet will help you out and tell you what to look out for. Look for the little purple circle on your map. They're called Asura Portals. The one in your starting city leads to Lion's Arch, the central city of the game where everyone hangs out once they finish things up in starting areas. From there you'll see 5 portals, each one leading to a starting city. Pick the one you want depending on the race you .

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