Physical build
http://wiki.guildwars2.com/wiki/Defiant
Bosses will get stacks of this immunity. As a group you could try and burn sacrificial CCs to land a specific CC you want. It seems I’ve seen some bosses that just generate stacks too fast to ever get through though.
Defiant is kind of two buffs. The first buff generates 3 (on bosses I’ve been aware of this at least) stacks of the second kind of “Defiant”. The first buff does not actually make the boss immune to CC, but the second buff does. Which means in bosses that I’ve seen, 1 in every 4 CC’s works. I’m pretty sure the 3 stack rule doesn’t apply to every single boss, and some just are immune period (WvW tower/keep defenders for example), but that’s what I’ve seen. Check to see which buff the boss has on. It’ll show up under their health bar.
Quaggan may or may not like you ~
You can still interrupt most bosses with those attacks even if it you don’t CC them (e.g. you can still trigger Distracting Strikes).
Immobilize, Cripple, and Chill will still work if you are trying for a control build.
thanks for the responses, I would check it so I wont waste time trying to leap to the boss to kick him.
Another note: Fear does not count as “CC” to the Defiant buff.
Quaggan may or may not like you ~