Stunning!
From Halopedia, the Halo wiki
Stunning!
Stunning! is an Achievement in Halo 3: ODST. It is awarded for disabling any Vehicles with an over-charged Plasma Pistol shot and killing the driver of the vehicle. It is worth 5 Gamerpoints. [1] It is easily obtainable in the missions Kizingo Boulevard and Uplift Reserve. It is recommended to turn the difficulty down to Easy or Normal to earn this achievement with ease.
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