Voodoo 1, Viper's on station. Your journey ends here, Pilot. The skies belong to me. Nowhere to run, nowhere to hide.
Viper is a member of the Apex Predators and a supporting antagonist in Titanfall 2. He dons a helmet similar to that of a Pulse Blade pilot, and utilises a heavily modified Northstar chassis, the spoils of a long and successful career as a mercenary. It is possible his callsign comes from the similarly-named Viper Thrusters, an upgrade available for Northstar.
Viper's only known role in the Battle of Typhon would be protecting and escorting the Ark to the IMC airfield housing the transport vessel IMS Draconis. He would later be seen, along with Slone, in the hangar of the ship prior to its emergency takeoff.
Viper would then take to the skies in his Titan, showing off an impressive array of upgrades allowing for vastly increased flight time and better missile tracking while fighting against squadrons of Militia Crows. Ultimately, he would fire a volley of missiles at the Widow housing Jack Cooper and BT-7274, causing them to fall through the skies and land on the dropship piloted by Barker.
Viper would continue to battle against the Militia's air forces, eventually making his way to IMS Malta in order to stop BT and Jack reaching the Draconis. The two Pilots would engage in a fierce battle on the outer hull of the battleship, with Jack ultimately winning and critically damaging Viper's Titan. With the two believing Viper dead, they would proceed to resume their attempt to board the Draconis, only for Viper to return and push them off the ship and into the sky. They would land aboard the hull of the Draconis and engage in a frantic melee. BT would tackle Viper, who would in turn activate his thrusters and plow BT back into the ground. Viper would then rip off BT's left arm, but have his own hatch shot off by the Vanguard. The exposed Viper would then be killed by Cooper with small arms fire.
There was originally a second Ronin Titan involved in this hectic exchange as seen in the E3 2016 Titanfall 2 Campaign trailer. Instead of BT tackling Viper after recovering from the fall, he would tackle a Ronin Titan, although the scene changes before anything else was revealed. What became of this Ronin is currently unknown. It is possible this Ronin was simply a stand-in for Viper, as to not spoil the boss fight in a trailer.
Viper has references and influences from Top Gun and Aliens.
His line "Viper's got you in the pipe, 5x5" is similar to a line said by Corporal Colette Ferro in the film Aliens, as the UD-4L Cheyenne dropship enters the atmosphere of the planet LV-426.
His mention of 'Voodoo one' is a reference to Top Gun, as is his callsign. In Top Gun the character Viper is played by Tom Skerrit, who also appeared in Alien.
Viper also makes reference to The Matrix by saying "Dodge this!"
Viper is the only member of the Apex Predators who never shows his face with the exception of Ash - who is a Simulacrum and does not have a face. He also is never called by his real name, unlike the other Apex predators.
His helmet was used for the original female Pulse Blade model during the tech test.
Viper's custom Northstar was the only one of it's kind which could fly for extended periods of time, such as an aircraft would.