This builds uses Deadly Arts hexes with Recurring Insecurity to degen kiters as they run.

Attributes and Skills

Assassin / Mesmer	Attribute Rank
Dagger Mastery	7 + 1 + 1
Shadow Arts	8
Deadly Arts	9
Critical Strikes	8
Illusion Magic	8

Recurring Insecurity

Scorpion Wire

Enduring Toxin

Jagged Strike

Black Lotus Strike

Signet of Disruption

Shadow Refuge

Resurrection Signet

Equipment

Barbed Daggers

Usage

Cast Recurring Insecurity and time Scorpion Wire and Enduring Toxin to extend its degen effects. Jagged Strike should stack the bleeding condition. Black Lotus Strike will help energy management. Use Signet of Disruption to interrupt any Hex removal spells.

Counters

If the foe is smart enough not to run while Enduring Toxin is active then you will have to finish him/her the hard way. Smite Hex and Zealot's Fire would hurt your team.

Variants

Any well timed Hex should work instead of the Deadly Arts ones.