Question about draconic bloodlines (SRD)

[lunar2]

So, i noticed that the major draconic bloodlines grant an (EX) breath weapon. the problem is, no limits on usage are listed. does this mean that the breath weapon is at will, or the same usage limits as an actual dragon? is there any precedent for usage of an EX ability missing any action description, or does UA provide more information than the SRD? i'm sure there are a hundred ways or more to abuse an at will EX AoE effect.

[Toliudar]

I acknowledge that having an (EX) breath weapon is a bit wonky, but a small cone of 6d6 damage at 16th level seems pretty difficult to break. I guess you could try to widen a persisted anti-magic field... I'm sure it's possible, given time and the scouring of splatbooks. Nevertheless, I'd allow unlimited standard-action use - or use the dragon's recharge mechanic if you prefer.

[Kuulvheysoon]

As a DM, I'd really have no problem with treating it as a 'regular' Dragon breath weapon, once every 1d4 rounds. There's even precedence for this (Dragon Breath feat, RotD). And really, 6d8 FIRE damage at 16th level really shouldn't be that much to worry about.

Although the (Ex) tag on it is more than slightly strange (given that a Dragon's breath weapon is given the (Su) tag).

[lunar2]

it's not so much the damage i'm worried about (and it's fire or cold, silver dragons get a major bloodline too) it's just the myriad ways to add various effects onto that breath weapon (antimagic field, as the example listed). seems like a potentially pretty impressive ability to be only part of the array given by a bloodline. and, because it's EX, the only way to stop it is to gag the user, which probably won't be very easy, since freedom of movement at that level is trivial to get.