Mudd with a weaponized dark matter sphere
Weaponized dark matter was dark matter that had been made into a weapon by converting it into a small sphere that could rip molecules at a subatomic level, thus killing an individual.
In 2256, Captain Lorca had samples of weaponized dark matter in his personal lab aboard the USS Discovery, and, when Harry Mudd used a time crystal to trap Discovery inside a time loop in a attempt to figure out the starship's secret and sell the ship to the Klingons, he stole the weaponized dark matter in one of the attempts to persuade the crew into helping him, or otherwise he would kill more crewmen. In one iteration of the loop, Mudd used some to kill Ash Tyler. In another, one portion was taken by Michael Burnham which she used to commit suicide to force Mudd to reset the loop again. Mudd claimed that death by weaponized dark matter was excruciatingly painful. (DIS: "Magic to Make the Sanest Man Go Mad")