Initial thoughts on PvP thief build (cond).
Good necromancers have always been scary as kitten, now they are insane.
Jump on the necromancer bandwagon; pressure-wise, they do everything better.
Inactive: Guardian, Elementalist, Ranger, Thief (ex-main)
Leveling: Engineer, Necromancer
The thing about taking a necro out is knowing when to bail to reset your utility skills.
When a necro goes into death shroud (green smoke with the ring), their hp is usually doubled. That complimented by the bleed, chilled, blind and life stealing skills, you have to watch your hp and speed. Good news is, they don’t stay like that forever so as long as you shadow them, they won’t heal all that much and then you can take him down. Just remember to avoid the marks and force him to fire his marks/wells at a distance. Remember, shadowstep and steal are great gap closers and add to the confusion as to where a thief is.