Cyber-bomb
Cyber-bombs were explosives used by the Cybermen, one being capable of destroying a planet and others supposedly capable of destroying a TARDIS. The Cybermen used Cyber-bombs despite the fact that they were banned by the Armageddon Convention.
The Cybermen attempted to destroy Earth in 2526 with a Cyber-bomb, but it was deactivated by the Doctor. (DW: Earthshock)
The Cybermen attempted to destroy Voga with Cyber-bombs, but the Doctor defeated their plan. (DW: Revenge of the Cybermen)
A group of Cybermen which had been transported to the Death Zone on Gallifrey tried to use several bombs to destroy the Doctor's TARDIS. (DW: The Five Doctors)