Yup, they are definitely fuzzy
And there doesn't seem to be any clear system, either. We have some powers (eg Delayed Blast Fireball) that have a secondary attack power written within the main power. Although the main power doesn't provoke, using the second part clearly is meant to. It has it's own "area burst" label!
And then other (eg Bigby's Icy Grasp) that have a standard action within the 'sustain minor' text. That "extra attack" (which costs an extra standard action) should surely provoke, right? But then are you using the power again (according to Dr_Ruminahui)?
But what about Mordenkainen’s Sword The extra attack (which, being a ranged power, should provoke) is now not only within the 'sustain minor' text, but is part of the minor action. The initial attack provoked, why should the follow-up attacks not?
How about Feast of Destruction, which has a 'sustain standard' which includes an area burst attack? Would you not make that provoke?
This one is pretty clear in my opinion - sustaining the power doesn't provoke; using the ranged attack secondary power does.
Both of these are conjurations. In my opinion, creating the conjurations provokes. Sustaining them / instructing them to make their attacks does not.
This one isn't a conjuration. When you sustain it, you make a new attack. I would say that provokes.
I should be clearer in my opinion: "Merely" sustaining does not provoke. If sustaining causes the caster (and not the caster's conjuration) to make a ranged or area attack, that provokes. Having a conjuration do something does not provoke. Those are just my opinions and my interpretations of the rules.
Yup hence my initial comment that powers doing more than 'just' sustaining definitely could be argued to provoke OAs.I should be clearer in my opinion: "Merely" sustaining does not provoke. If sustaining causes the caster (and not the caster's conjuration) to make a ranged or area attack, that provokes. Having a conjuration do something does not provoke. Those are just my opinions and my interpretations of the rules.
Actually, the rule is:
That is, it's not the attack that provokes, but using a ranged or area power. Ranged utility powers (that are not attacks) still provoke.
Now - as to what "using" is, that is a much more fuzzy topic. Sustaining a ranged power, especially when the power does something further, definitely could be argued to still be using it, and thus would provoke an OA.
Using a power is a specificly listed action and is distinct from sustaining it. If sustaining a power were the same as using it, you could never sustain a non-at-will power because it can only be used once. As well, it would require the same action as it took to activate the power in the first place, as both these things are keyed to using a power.