No Introductions needed, so i'll get right to the chase.
The 2-shot Kill TR, basically focuses on stealthing for as much as possible, as well as Action Point generation, so that you can get as many Shocking Executions in a game as possible. Below I have my personal view on what you could choose. Powers are basically really based on what the enemy team is consisted of, and your playstyle.
I'll leave Powers later on for some theory-crafting...
On to the Feats.
HEROIC FEATSAction Advantage 5/5:
More Action points when dealing Advantage Damage. Since you are almost 99% dealing advantage damage, (stealth, they are focusing someone else, flanking them) who would give up free Action Points?
Weapon Mastery 3/3:
More Crit, thank you very much.
Toughness 3/3:
Hp is very critical, and since you are going to be stacking HP with PvP items, this gives them an extra boost as well.
Cunning Ambusher 3/3:
Due to the fact that this is a Stealth build, this is almost mandatory. More damage output on your first 2-3 skills.
Twilight Adept 2/5:
Time to start getting some survivability skills, this one allows you to get in stealth faster, especially since the dodge roll is spammed more than an On-Will ability on this game.
Improved Cunning Sneak 4/5:
16% More stealth is not at all bad.
PARAGON FEATSSpeed Swindle 5/5:
Because a 20% speed difference between you and your opponent can make turn the tables in tight situations. Both chasing and avoiding.
Cunning Stalker 5/5:
More action points in a state where you are going to be 50% of the time when in Combat.
Underhanded Tactics 5/5:
20% more damage almost all the time. Yes please.
Nimble Blade 5/5:
If you don't crit you just hit them harder. A lot harder.
Mocking Knave 5/5:
Sly Flourish and Cloud of Steel are your 2 On Will skills. Sly Flourish, also sorta "chases" the opponent, whereas on Duelist's Flurry you just sit like a rere slashing the air. Cloud of Steel can almost kill an CW/TR when all 12 stacks are unleashed on them.
Action Rush 5/5:
You have a 15% chance to get an extra 15% of your Action Bar with any Encounter. This is essential since your goal is to spam Shocking Execution as much as possible. This works even better when using spammable Powers like Wicked Reminder or Impact Shot.
Whirlwind Sneak Attack 1/1:
Not really as "Epic" as it's gold border wants it to be, but meh... at least you get to see nice numbers with Lashing Blade
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Your skill Bar.
Now... This is subjective on how one wants to play, and what you're playing against.
If you have a bunch of CW's and TR's in the enemy team, you NEED to go melee. You are more of a threat when you're slashing their garbs with your daggers than when you're poking them with your throwing knives.
On the other hand, if they have at least 2 GWF's, you want to keep your range from them. So on your Action bar you want other than the
MUST HAVE Sly Flourish and Cloud of Steel, you will want to have Impact Shot.
Lashing Blade is the one that is going to be getting swapped out for others. I will explain why below.
My Action Bar sets are usually like this:
Or
Smoke Bomb is a lot better than your Dazing Strike for 2 main reasons. It doesn't have to land on someone to cause them to get dazed for 2-3 seconds (even when you have walked out of it you still remain dazed for a coupe of seconds), and it is AOE. And a pretty large one at that. It will cover almost, if not more, half of the radius of the base of a Point that you need to hold.
Now, one will ask "why change lashing blade when it's a high burst ability?". Simple. If you are having around 200ms ping, just because you live in the EU, you will get extremely frustrated as to how many Lashing Blades will seem to have hit, and they just don't. So, by swapping out Lashing Blade with Impact Shot, you get a ranged ability that ALWAYS HITS(unless dodged, but that affects almost every other ability in the game) and it also has 4 stacks when one of them is launched through stealth. More stacks = More Action Points + More chances of getting another 15% due to the Feat. Execute Often. Gloat a lot more often.
Shadow Strike is an amazing skill for both infiltrating almost undetected to release your carefully set Smoke Bomb right in the middle of those CW/DC's, as well as avoiding difficult situations where a GWF's only goal is to chop you up.
Your Passives are
Tenacious Concealment and
Skillfull Infiltrator. You will find yourself getting hit while stealthed basically most of the times... it will be a shame to lose all that stealth that took you so long to build up. Skillfull Infiltrator just because 15% stealth and 3% crit are also pretty useful.
How to play.
Unfortunately there is no rotation or whatever when in PVP, especially when PvP at this point is zerging the enemy. By going all out on 1 of the 3-4 that are going to be on 2, you immediately give the advantage to your team, and you still can help out with your smoke bomb, as well as with your auto-attacks until you get another Lashing Strike or a stack of Impact Shot up.
This is subject to change if they decide to change the way Shocking Execution and Lashing Strike works. But I highly doubt it for the time being.