Z-Neutrino Biological Inversion Catalyser
The Z-Neutrino Biological Inversion Catalyser was a device created by the Meta-Crisis Tenth Doctor shortly after his 'birth' in order to destroy Davros and his Daleks.
History
The Catalyser was created from pieces of the Doctor's TARDIS and designed to lock the transmission of the Reality bomb onto Davros in order to kill him and the Dalek army that he had grown from his own cells.
The Doctor's double arrived on the Crucible but before he could fire the weapon, he was incapacitated by an energy bolt from Davros' cybernetic hand. Donna also attempted to use it but was also incapacitated by Davros while asking how to fire it. Upon Davros' orders the Inversion Catalyser was then destroyed by a Vault Dalek. (DW: Journey's End)