Actually, I wouldn't grant an attack of opportunity against a held spellcaster casting a still/silent spell. You have to think of what the idea behind AoO is ... if you are in a "combat situation" with someone, both sort of on guard vs. each other, and one lets his guard down, the other gets an "extra slice". A held person is no longer in combat in any real sense.
However, by this idea it would be perfectly reasonble to grant an AoO against a held character teh round they became held if someone was "in combat" with them, since becoming helpless certainly counts as letting your guard down. I wouldn't allow this for the same reason I imagine it's not a rule ... as was stated above you're already pretty screwed getting held or paralyzed.
For the same reason it might be reasonable to allow an AoO every round against a held character in a complex fight, but I wouldn't allow it for balance.
These rules are just a really rough approximation and simplification anyway. As many will tell you they try to model complex fighting with the system not individual swings ... however, this of course really breaks down with ranged weapons anyway.
However, by this idea it would be perfectly reasonble to grant an AoO against a held character teh round they became held if someone was "in combat" with them, since becoming helpless certainly counts as letting your guard down. I wouldn't allow this for the same reason I imagine it's not a rule ... as was stated above you're already pretty screwed getting held or paralyzed.
For the same reason it might be reasonable to allow an AoO every round against a held character in a complex fight, but I wouldn't allow it for balance.
These rules are just a really rough approximation and simplification anyway. As many will tell you they try to model complex fighting with the system not individual swings ... however, this of course really breaks down with ranged weapons anyway.
