Ambushes in WvW
Thieves do this already. It only works on 5 people (I think?) and can stealth them for about 8 seconds.
I don’t know about the limit tough, but yes thieves can do this.
I wonder if the trait for +1s stealth applies to allies.
Usually when i use it on myself I’m stealthed for 12s, tough usually allies attack or run out of the circle beforehand so i don’t know the time.
Ex
i forgot about the smoke ring thing, but that is a combat thing and very short. I was thinking about something out of combat and that would last much longer to help set up for attack