A full-auto pistol known as the most compact and lightweight weapon of the Grineer arsenal. Though it has a small clip size, the Viper has a very high fire rate and ultra-fast reload times thanks to a simplified magazine design.
The Viper is a machine pistol of Grineer design issued to their Shield Lancers. It is the most portable weapon manufactured by the Grineer and boasts a high rate of fire and an extremely efficient magazine reload, but poor accuracy.
Some have experienced bugs with this weapon's reloading. Try and stop pressing the sprint button while you reload. For some reason if you reload and sprint at the same time you might have some problems with fast reloading weapons. NOTE: This reloading glitch can be caused by game lag and low framerates, and can become so troublesome you can stand in place and it will constantly do the reload animation indefinitely or until lag improves. It is not recommended to use this weapon if you have problems with lag or framerate issues as this may become near useless in combat.
Although it is not recommended for long range fighting, correctly aiming and tapping the trigger will expel 1-2 bullets at once, and you may get a decent critical or headshot rate by doing this.
The Viper was released on the 18th of March, 2013 with Update 7.
On the Viper's barrel, the word "Viper" is inscribed in the Grineer Language. In earlier versions of the game this line of text was "Serberus", probably indicating an earlier name for the gun. The Viper's UI icon still shows a Viper with "Serberus" inscribed on it.
The Viper(s) uniquely has a distinct sound when its trigger is released. This could be a mechanism used to stop the bullet feed or to halt the cyclic action.
Shield Lancers fire their Vipers in three-round bursts, a holdover from when Shield Lancers used to be equipped with the Sicarus.