The spell is designed to force concentration rolls for spellcasters, by being a loud and noisy distraction (one roll, not several). The smoke is thick enough to block vision for a moment, making things that require sight of the target difficult at best. The noise and light are enough to startle (think, firecracker), but not damage.
As the spell is a Creo spell, it can have either a target of Individual, or Group. Since the spell is designed to effect a relatively small area, the base group of 10 suffices...Wait a minute... Those are some HUGE clouds of smoke...an indiviudal aurum effect covers an area 100 paces across!
I could reduce the target to individual - an area that is roughly 100 paces across for Aurum - and still fill the area with smoke puffs, the effect of smoke puffs being largely cosmetic.
Penetration shouldn't be a problem now, given the spell's low level. Most of the people who can cast it have pretty good arts scores, at least at our covenant.
Redone...
Flare Bit, Creo Aurum, L10
Base : 3 (Create Debilitating Air, in this case, thick black smoke)
Range : Voice (+2)
Duration : Momentary(+0)
Target : Individual (+0) (an area of up to 100 paces across)
Other : Ignem Requisite (+1) (Flash of light, enhances spell effect)
The spell, when cast, fills an area with smoke, which appears as a series of thick, black puffs of smoke. They appear with a loud report and a flash of light, which serves as an excellent distraction, forcing a concentration roll (only one), if required. The smoke is thick enough to block vision for a moment, making such things that require sight difficult as best.
The smoke starts forming around the center of the area, and works it's way out to the edges. The smoke disperses normally, though natural phenomena my cause it to disperse more quickly.
Another version of this spell exists at L5, and does not have the Ignem requisite (and does not produce a flash of light when the smoke is created).
Steve