Chainsaw

A chainsaw was a tool that could be used as a weapon.

Rhys Williams attempted to use a chainsaw on a Nostrovite, but it failed to work. (TV: Something Borrowed)

Rose-the-cat once removed a section of the TARDIS' wall with a chainsaw in the hopes of making a cat flap. This caused disturbances through all of time and space, such as a unicorn rescuing Richard III when he asked for a horse in 1845, the Beatles turning into violent, howling wolves while performing "I Want to Hold Your Hand" in 1961, and the actor who was playing Russ suddenly turned into a frog during the filming of the final episode of Chums in 2014. The hole was then patched with duct tape, which seemingly fixed the problem. (COMIC: A Rose by Any Other Name)