How does cry of frustration work?

How does cry of frustration work? What types of spells/skills/signets/actions can it interrupt? I just finished a mission vs. Kuunavang, and CoF couldn't interrtupt any of his special abilities.

Kuunavang is a special case and seems to be interupt resistant. You can interupt it, but often it only happens on the second or third interupt.

As to the question, CoF can interupt anything with a cast time.

well, COF can interrupt any skill, but special abilities must not be skills; mostly because they just want to make the game slightly more difficult, which they achieved in 2 pretty lame ways in factions:
1) throw giant waves of enemies at you that have rediculous abilities like built in death novas
2)create boss monsters that can't be interrupted or knocked down, hit for insane amounts of damage, and have special powers that you can't have.

easier than increasing A.I. I suppose.

his monster skill corrupted spores or whatever only seems to be susceptible to dazed interrupts, at least on a ranger. I havent played around with mesmer skills, but I'd bet leech signet would work every time as it interrupts target foe's action and not just skills. try a keystone signet build ftw ;P

Sheesh Thom, whadya want its 1 vs 16....

Name one major RPG where all monster enemies have no inherent bonuses and can only use the same skills players can.

Anyways, cry interrupts any skill used (and triggers aoe skill interrupt upon that). Kuunavang just takes a few interrupts at times, I don't think there are any other mobs that act like that.

Kuunavang creates six spores, every time she's interrupted she makes two spores less, meaning you need three interrupts to cancel it completely. Also, I think dark chain lightning is uninterruptable, but I've never played interrupter against her so I wouldn't know for sure.

Dwarven Battle Stance FTW

Monster kills are skills too, and can be interrupted by interrupts that target skills (not spells), provided that the targeted skill has an activation time >0.

Kuunavang is a special case. It is one of two monsters I'm aware of that has a special resistance to interrupts (the other being the Lich Lord). Interrupts work against Kuunavang, but most of the time you need more than one interrupter to make them work. Either a certain minimum of interrupts is required (two or three?), or there is a random chance (50%?) of an interrupt to fail. I'm not sure.

just ignore me, I PVP too much.

You need to hit with a 'disable skill / spell for ... seconds' spell (like rangers distracting shot).
Only Mesmer spell to do this is Power Block (elite) afaik.
Tyggen is most probably right on the 3 'regular' interrups for the given reason.

psychic distraction does that too, and is a lot better.