Gravity wrench
From Halopedia, the Halo wiki
The Gravity Wrench was a deleted Covenant weapon intended for an early version of Halo: Combat Evolved. It may have provided a titular basis for the Gravity Hammer. It may have also inspired the Plasma Pistol, as the weapon must charge and then fires a strong ball of energy. In addition to that, it appears to act like a flamethrower, or other Support Weapons.