Invasion of Time saw Commander Stor using the small rod again, but also in episode six, a Sontaran trooper uses a short black rifle-like laser to try to burn through a lock on a door inside the TARDIS. The Two Doctors introduced a weapon called the Meson Gun (as named in the Jim'll Fix It Sketch, A Fix with Sontarans), a large silver rifle with a red fuel tank in the centre which was used by Group Marshal Stike and Varl in the third episode. It seemed to be some kind of flamethrower as it fired a jet of flames very briefly. Group Marshal Stike was also seen carrying a baton. It would not be until The Sontaran Stratagem that General Staal would show that the baton can fire an orange beam that could stun the target. In The Poison Sky, Commander Skorr and his troops carry large laser rifles into battle. These rifles are the Sontaran gun of the Tenth Sontaran Battle Fleet. Each rifle has a laser beam that kills instantly and is designed for a three-fingered grip. In The Invasion of Time, their armour is shown to be resistant to Time Lord stasers and K-9's blaster. However, their armour is vulnerable to standard human firearms in "The Poison Sky", but the Sontarans in that episode used a 'cordolane signal' which caused the copper-lined bullets to expand, jamming most firearms instantly. UNIT troops overcame this by switching to steel-lined bullets. The Sarah Jane Adventures story The Last Sontaran showed further technological advancements of the modern Sontarans. Commander Kaagh, a surviving pilot from the Tenth Sontaran Battle Fleet, had slightly different armour due to being from the special forces. His suit featured no gloves, so his bare hands were visible, and on his left arm was a control panel for his suit and ship. His helmet could fold up and retract and both his suit and ship featured cloaking devices, turning them both invisible. While the soldiers of the Tenth Fleet were armed with large laser rifles, Kaagh has a smaller laser carbine. Rather than hypnotising humans (as Sarah pointed out they usually do), instead, Kaagh fixed neural control devices to the back of the necks of his human agents. A red light flashes when it is operational, and Kaagh can activate and deactivate them when he wants with his control panel. A pair of Sontarans that tried to