A friend asked for mine a short while ago so I thought you may appreciate a copy/pasta. The videos showcasing it in action are from quite a few updates ago, however not enough has changed for that to really matter on how this build works. As long as you know what to avoid (and are adept at avoiding them) then its only inherent weakness is other Thieves - mainly D/P or other stealth-camping weenies. Though a Target Painter will give you the edge you need there, at the cost of incessant whining from your victim.
http://gw2skills.net/editor/?PayAQxrlNwkYbMQGJOMXnvKA-zVZYBBZME1jY4yPlwUItJJaVE1rQUjHgA+rRAzAA-w
-Open with Mark, skirmisher's shot 3 to 4 times to trigger M7. Use stolen skill to gain stealth, DJ to dump Malice and deal chunk damage. If DJ misses, don't spam skills, shoot one or two spaced Skirmisher's shots in between your auto attacks just to make it so you don't get full initiative, wait for reveal to fade, gain stealth again by dodging, stolen skill, or elite and DJ again.
-Mercy is very often used offensively even when not stunned, it refills initiative when you are having a hard time landing DJ, and gives you immediate access to Mark again (damage, heal, interrupt, 3 boon steal, poison, weakness, vulnerability, might, fury, swiftness, vigor, and quickness (quickness only if it has been 20s since last rifle-wielding mark due to Sigil of Celerity)
-Smoke Screen is used immediately as a preemptive defense vs ranged projectile enemies. If you are not being attacked by ranged projectiles, it is used as soon as a melee player enters your space. It provides excellent mitigation on a 1s pulse unblockable AOE blind, all Skirmisher's shots fired through it will carry a blind, and 20% of auto attacks will carry a blind. If you are getting overwhelmed and your smoke screen is active, you can Rifle 4, Death's Retreat, to get out of melee range and gain 3s of stealth
-Shadowstep can also be used offensively to gain unobstructed line to the target, see this video at 35 seconds in to see how I noticed that the 2nd enemy or his clones would block Death's Judgement, so I Shadowstepped immediately after gaining stealth to fire from an open angle:
Here is a general video that is long enough to showcase damage, defense, reactions, repositions, etc:
-You'll notice that I target clones and use DE Mark. This is intentional as the mark refreshes when the target is killed/destroyed. Clones have low hp - power Mesmer clones are destroyed just by the mark alone, and it gives initiative, regen, might, fury, vigor, healing(Mug), and potentially resets a cooldown w/improv. Condi/tank Mesmer clones take one mark and then one F2 (stolen skill). This strategy allows for multiple Mugs to heal you up and refill your initiative.
-When projectile hate or line of sight is preventing you from doing Rifle damage, immediately swap to S/P and use Sword2, Sword3 to port in, immob the target, and then chunk their HP with pistol whip. Generally you will need to sword2 again right after pistol whip is done to avoid counter-pressure in melee range.
I also have a variant copy of this build that uses anti-toxin runes and two rifles, both with sigil of energy and sigil of cleansing. Your damage and hp are slightly lower, but you're extremely resilient against condition-based opponents, which is why I didn't list condi thieves as one of my build's weaknesses.
