SRD:Dissipater

Dissipater: This kind of weapon is devastating to creatures and objects composed of or originally formed from ectoplasm (such as astral constructs, walls of ectoplasm, creatures in ectoplasmic form, and items created using the metacreativity discipline). Against qualifying targets, a dissipater weapon ignores damage reduction and hardness, and treats all successful hits as critical hits.

Strong metacreativity; ML 12th; Craft Psionic Arms and Armor, dismiss ectoplasm; Price +1 bonus.