The Charging Needler Glitch is a glitch that works on the Halo 2 level, Sacred Icon and during Halo: Reach Firefight as a Covenant ally. It can only be done when you have Jackals as your allies with a Plasma Pistol in their hand and an opponent nearby.
Destroy all the Sentinels and the Sentinel Launchers to stop any Sentinels from coming out. If the Jackal is charging his Plasma Pistol after the battle, switch it with a Needler. If done right, the Needler will fire, but no Needles will come out. Try it with other weapons such as the Plasma Rifle, or any other weapons you can find. If you give him the Plasma Rifle, he will fire and overheat it.
To experience this glitch, a Covenant enemy must approach a Jackal until a certain distance. If this distance is correct, the Jackal will charge its Plasma Pistol. When this happens, a Covenant ally must approach his/her ally and change this overcharged Plasma Pistol with his/her own Needler. When this glitch is performed, the Needler the Jackal is holding has the same ball of light in front of the Needler as with a Plasma Pistol, but it is pink. Also the sound it produces bears close resemblance to alternating double wielded Needler fire possible in Halo 2, although faster.