Hyena Pack

The Hyena Pack are the final bosses of the Neptune system. They can be found on the mission Psamathe. After defeating them and finishing the mission, you receive either a Loki Helmet, Loki Chassis or Loki Systems blueprint. Upon death, all the Hyenas have a chance of dropping Control Modules.

Appearance
Each Hyena possesses unique colour scheme and set of abilities. There are four unique variants, each named after a chemical element or compound that reflects their abilities. Unlike other bosses, the Hyena Pack appears in specific standard rooms instead of a special arena; however, like other bosses, the pack taunts the players during the mission and has its own opening cinematic. Here is a list of their taunts:

Pre-Battle During Battle Hyena Destroyed
 * "The Pack is watching you"
 * "The pack can smell you"
 * "The pack grows excited, we have been waiting for this."
 * "The pack call for your death."
 * "The Pack says: 'kill them off one by one' "
 * "The Pack says: 'kill the weakest one first' "
 * "The pack will sing when you die."
 * "The pack is designed to enjoy this, It is in its circuits."
 * "Hyena disabled: The pack will intensify the hunt."
 * "Hyena disabled: The pack grows weak."

Abilities
The Hyena Pack, true to the intel, work in packs of up to four with each of them possessing a unique set of abilities. Each Hyena possesses a plasma repeater and are far more agile than any other enemy in the game, including Zanuka and Harvester. Alongside their agility, they can also jump on to and cling to walls, though they cannot wallrun.

LN2 (Liquid Nitrogen)
Hyena LN2 (Liquid Nitrogen) by default deals Damage, it is geared with a Freezing Aura, which constantly inflicts Cold proc nearby, drastically slowing down those in its victinity. It is also capable of releasing a path of icicles towards it's target, akin to Frost's Ice Wave; this guarantees Cold proc and inflicts significant damage.

Pb (Lead)
Hyena Pb (Lead) by default deals and  Damage; it does not have any specific elemental effects or powers, however it possesses high firepower. Besides its plasma repeater, it can also perform Lead Whirlwind, where it will jump about a meter into the air and spin around to fire a large number of projectiles in all directions as an anti close-combat measure; Lead Whirlwind can inflict Proc.

Ng (Nitroglycerine)
Hyena Ng (Nitroglycerine) by default deals Damage; armed with heavy AoE firepower, it will also occasionally fire a volatile Nitro Bomb capable of knocking down the player. It is also capable of lighting a path of ground on fire similar to Lech Kril's Fire Wave, which guarantees Fire proc. Its bullets can also randomly proc Fire.

Th (Thorium)
Hyena Th (Thorium) by default deals Damage and has a constant Disruption Aura. Simply being near it will induce the Magnetic proc, scrambling the screen and instantly draining all energy as well as a large chunk of shields. Its special attacks include Electric Surge, a wave of electric carpet that travels quickly across the ground, and a Shock Bolt that guarantees Electric proc, as well as being able to charge akin to Slash Dash within a close distance (knocks down on hit).

Strategy
The Hyena pack is capable of taking a beating. They all have hard hitting attacks, and if not careful, you will have no energy for any abilities. A loadout containing and or  damage is recommended in order to deal with the the Hyenas effectively.

As with other bosses, it is important to eliminate surrounding grunts first before targeting the Hyena pack, which is even more important due to the hyenas seemingly buffing them.

Taking out Hyena Th should be your primary concern due to its Disruption Aura being capable of instantly draining shields and energy upon proximity, while Pb will be of least concern due to lack of special capabilities at long distance.

Always try to keep a medium-long distance when fighting against Hyena Th and Pb. The reason being Hyena Th's ability to constantly drain shields and energy, stripping you off your primary means of defense and utility. The other reason being Hyena Pb's extremely high amount of firepower, tanking Hyena Pb's bullet spray at close proximity will ensure heavy damage (if not death) as well as almost-guaranteed /  proc.

Due to their firepower, high shields, and high health, it is somewhat difficult for an unprepared Tenno to beat the Hyena Pack alone. Being able to sustain damage against the shields is vital, so weapons with high impact damage, like Gorgon or Karak are vital. If you are lacking these, a gun with the magnetic element attached can take the place.

As is the standard strategy against multiple difficult foes, Divide and Conquer. Focus on one Hyena at a time and stay away from the others.

Due to Th's Disruption Aura, having a Trinity to cast Energy Vampire is a great way to recover energy. However, ability usage is still relatively unreliable in this fight, so tanky frames like Rhino and Valkyr may do better over glass cannon casters like Nova.

Trivia

 * In earlier versions the Hyena was said to be a new Corpus proxy that hunted in packs. However, you only fought one during the mission. This was eventually fixed and then changed in Update 12 with the Hyena finally becoming a pack boss.
 * For that matter, prior to Update 12 the Hyena was essentially a scaled-down Jackal in both size and firepower.
 * Each of the Hyenas is named after a chemical element or compound that reflects their abilities, with Th (Thorium) being the only exception.
 * LN2 (Liquid Nitrogen) is nitrogen in a liquid state at an extremely low temperature as low as −196 °C (77 K; −321 °F) which reflects Hyena LN2's power above ice abilities.
 * Pb (Lead) is one of the elements most commonly used for bullets which reflects Hyena Pb's extremely high amount of firepower.
 * Ng (Nitroglycerine) is a heavy, colorless, oily, explosive liquid commonly used in explosives like dynamite, reflects Hyena Ng's explosive firepower.
 * Th (Thorium) is a naturally occurring radioactive chemical element which is paramagnetic (slightly affected by magnetism); while this (somewhat) explains Hyena Th's magnetic properties, its electrical attacks may be a reference to the element's namesake.
 * The Hyena Pack is the only boss that consists of multiple entities. Originally the fight always consisted of all 4 Hyenas at once, but this was later changed in favor of scaling with player number, with solo attempts getting two randomly chosen Hyenas.

Bugs

 * The Pack presently lacks its own Codex entry, either for the group as a whole or the individual units. Scanning them still awards XP.
 * Hyena Th's electric attacks often leave particle effects on the map that don't naturally dissipate.