Mercy

 is a unique 40mm grenade machinegun in Fallout: New Vegas.

Background
A veritable relic, Mercy is a pre-War US Army automatic grenade launcher that was used by one of the US Army's counter-insurgency units hunting Chinese Hei-Gui commandos in the American south-west, and one of its operators spray-painted Hei Gui Bye Bye on the chassis. At an undetermined time it was obtained by the Brotherhood of Steel and continued to serve as a weapon, eventually ending in the hands of a Paladin in the Mojave chapter. It was lost when its operator fell while exploring the Dead Wind cavern.

Characteristics
Its higher damage comes at the cost of using 40mm grenades, which are less common and more expensive than the 25mm high explosive grenade. It cannot be modded. The larger size of the 40mm grenades also restricts its ammo capacity to 18 grenades, which is 12 less than the regular Grenade machine gun.

Variants

 * Grenade machine gun

Location

 * Dead Wind Cavern - By a dead Brotherhood of Steel soldier along with some 40mm grenades, 40mm incendiary grenades and T-45d Power armor and helmet. It is guarded by various types of Deathclaws and the Legendary Deathclaw.

Bugs

 * The game may crash if you fire continuously in the same place

Behind the scenes

 * The name Mercy is most likely a reference to the modern artillery operation called Multiple Round Simultaneous Impact or MRSI which is nicknamed mercy. It consists of automatically firing explosive rounds in a volley at the enemy, which is effectivelly what mercy and the grenade machinegun do. Also, when a howitzer or similar weapon uses MRSI the end of the barrel usually 'pumps' as it fires the rounds, similar to the grenade machinegun and its variants.
 * The location and name of the Mercy could be a reference to the unique Gatling Laser in Fallout 3 called Vengeance, like the Mercy, the weapon is found in a location that is full of Deathclaws.

Gallery
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