The Sergeant

Sgt. Nef Anyo is the final boss of Mars system. He can be found on War. He has a possibility of dropping one of the following on death: Mag Helmet, Mag Chassis and Mag Systems blueprints, and Gallium or Morphics.

Appearance and abilities
Nef Anyo resembles a Corpus Crewman Sniper, though with some aesthetic differences, such as being slightly larger, having a red visor and having a black suit instead of a brown one.

He wields a sniper rifle, which has a very low fire rate but extremely high damage, hitting up in the 200s per shot and causing knock down. He also has the ability to turn invisible with a cloaking grenade, disappearing for a few seconds and turning up elsewhere.

Strategy
Nef Anyo is found in a wide open outdoors area filled with cargo boxes. Upon entering the area he is in, prioritize destroying all other enemies and isolate Anyo. While his rifle deals high damage, it bears a characteristically low fire rate in turn, so keep moving amongst cover and zigzag to avoid being shot. Once Anyo is isolated, he is a cakewalk. Just like normal Corpus crewmen, he is extremely vulnerable to electricity, and using weapons with electric damage mods can keep him stun-locked almost permanently. Just keep pounding away until he dies. An upgraded Gorgon with shock and armor pierce mods is capable of killing him in 5 seconds.

You can track his location while cloaked with the Enemy Radar. Setting him on fire also works.

Trivia

 * Nef Anyo is in charge of the Corpus solar rail systems, and has been using them to obtain Cryopods with dormant warframes for resale to rogue scientists and splinter groups. He was targeted for assassination so that the cryopods can be rescued.
 * Despite being the second Corpus boss after the Jackal, due to his vulnerability to shock damage, low shields and low health, he is arguably the weakest boss in the game, even weaker than Captain Vor.
 * He used to have a red visor, but now has a blue one like regular crewmen.
 * He is the only boss along with Kela De Thaym without a cutscene.
 * Surprisingly he gives the same amount of Affinity as Crewmen with the same level.
 * Prior to update 7.7.3, there was a glitch where when Nef Anyo cloaked himself, he never uncloaked again, making it difficult to fight him without an Enemy Radar.