Compare to the archetypal 2nd-level damage spell, Acid Arrow:Scorching Ray
Evocation [Fire]
Level: Sor/Wiz 2
Components: V, S
Casting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Effect: One or more rays
Duration: Instantaneous
Saving Throw: None
Spell Resistance: Yes
You blast your enemies with fiery rays. You may fire one ray, plus one additional ray for every four levels beyond 3rd (to a maximum of three rays at 11th level). Each ray requires a ranged touch attack to hit and deals 4d6 points of fire damage.
The rays may be fired at the same or different targets, but all bolts must be aimed at targets within 30 feet of each other and fired simultaneously.
Acid Arrow
Conjuration (Creation) [Acid]
Level: Sor/Wiz 2
Components: V, S, M, F
Casting Time: 1 standard action
Range: Long (400 ft. + 40 ft./level)
Effect: One arrow of acid
Duration: 1 round + 1 round per three levels
Saving Throw: None
Spell Resistance: No
A magical arrow of acid springs from your hand and speeds to its target. You must succeed on a ranged touch attack to hit your target. The arrow deals 2d4 points of acid damage with no splash damage. For every three caster levels (to a maximum of 18th), the acid, unless somehow neutralized, lasts for another round, dealing another 2d4 points of damage in that round.
Material Component: Powdered rhubarb leaf and an adder’s stomach.
Focus: A dart.
Pielorinho said:And IMC it's been cast only once so far, compared to the ubiquitous Melf's spells. Even then, it's cast nowhere near as often as Web or Glitterdust, the true powerhouses of second-level wizard spells.