Requirement: Perform 3 ranks
Base effect: Whenever an ally within 30 feet successfully damages a creature or object with a melee attack, the DR or hardness of the target is reduced by 2 while the siren maintains this maestro performance. This effect does not stack with itself against the same creature or object. The amount of reduction becomes 2 points higher at 5th level and every 5 levels thereafter (to a maximum reduction of 10 at 20th level).
You summon corrosive acid in a 15-feet emanation centered on any creature within medium range. The creatures in this area suffer acid damage, which is halved on a successful Fortitude save.
Weak Refrain: Creatures in the area suffer 1d4 points of damage per siren level (max 4d4).
Intermediate Refrain: Creatures in the area suffer 1d6 points of damage per siren level (max 8d6).
Strong refrain: Creatures in the area suffer 1d8 points of damage per siren level (max 12d8).