No idea where to start
Backstab is your autoattack when stealthed. Your normal attack is toggled into a powerful attack when you hit someone from behind while stealthed. You can get stealthed from the heal Hide in Shadows, from Cloak and Dagger on dagger offhand, from using heart seeker through black powder, from several utilities, etc etc..
To start out, try running dagger mainhand, pistol offhand with a shortbow for backup. I think the best newbie build for that is 2/6/6/0/0.
http://gw2skills.net/editor/?fZAQNAoaVlsMpyplOx7J8PNBNBt9DGeE4uGlYGaFAA-TZRBwAReCA02fgcZAAHCgHnAAA
Cast #5 to get a small AOE circle beneath you that blinds anyone inside of it then heart seeker (#2) through it to gain stealth and try to backstab the opponent. Keep practicing that combo till you get good at it. A cool trick is to hit backstab while far away from someoen and quickly hit steal and the mug damage as well as the backstab damage will connect for a big hit.
When you get better you can try 2/6/0/0/6 with the same gear (except I’d use ogre runes instead). This build has a lot more damage/utility but it’s much less survivable.
Hope this helps.
Highest Solo Queue Rank Achieved: 40
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