Ambulas

Ambulas is the boss of the Pluto system. It can be found on the mission Hades. It has the possibility of dropping one of the following on death: Excalibur Chassis, Excalibur Helmet, and Excalibur Systems blueprints, as well as Morphics. Upon the release of Update 6, It replaced Arn Etina as the Pluto Boss.

Appearance and Abilities
Ambulas is a small black MOA unit. While unremarkable in appearance, it is extremely fast and has a variety of abilities.

Offensively, it has a machine gun that deals high damage, about 35 per shot. While it usually fires in single shots, it can also fire a continuous burst, particularly when players are knocked down. It also has a stomp attack, though unlike other enemies, Ambulas' stomp attack does not result in a knockdown shockwave, but a Ring of Fire that deals insane amounts of damage to any player within the area of effect, quite capable of ripping down 700+ shields and health in seconds. In close quarters, it can use a Kick that will knock players down. In addition to all this, it has an ability similar to Mag Pull, which it will use often and chain with the Ring of Fire or Kick.

Defensively, it has moderate shields with a moderate recharge rate, though its recharge delay seems to vary at times. It has a decently large health pool as well, though not enough to be a bullet sponge.

Ambulas, like many other bosses,has unique taunts. Here is a list of them:
 * "Incursion Probability: Negligent. Tenno Mortality Probability: Inevitable."
 * "Offensive System Conclusion: Enemy Combustion."

Strategy
As with all other bosses, kill all nearby mobs before engaging Ambulas. This being Pluto, the last thing you want is several high damage machine guns blasting you while being chased by the boss.

Due to its Ring of Fire and Sparta Kick, both being close quarters abilities, you would do well to stay away from Ambulas and kite at a distance. However, what makes Ambulas difficult is its extremely annoying Pull ability, which it WILL spam every time it gets the chance, and will most likely follow up with an immediate Ring of Fire or Sparta Kick. The Pull ability is unavoidable, and the only way to keep it from triggering is to stay out of Ambulas' line of sight, which doesn't work very well since you can't shoot it by doing so.

The Ring of Fire attack activates on its own timer, which starts out synchronized with the Pull's cooldown. It is possible to un-sync this timer by staying out of Ambulas' line of sight temporarily, so that it will automatically use Ring of Fire without using the Pull, thus un-syncing their cooldown timers. This at least reduces the chance of Ambulas being able to follow-up a Pull with an immediate Ring of Fire.

Keep a good stock of energy and use it on escape-related skills for when you get Pulled. For example, Excalibur's Slash Dash, Rhino's Iron Skin and Trinity's Link are good abilities to help you escape/survive a Pull and Ring of Fire combo.

As a Corpus unit, it is weak to electrical damage. Also, due to its devastating close range abilities, shotguns are not advised for this fight.

Exploit
Jumping on a double crates can potentially disrupt Ambulas' targeting, making it a sitting duck. It is also possible to get it stuck on stairs, though in most such cases it'll just use a Pull to drag you to it.

Trivia

 * Pluto's boss was called 'Arn Etina' prior to Update 6.  His picture showed a cyborg face, however this was replaced with his current model.
 * Ambulas is currently the only boss to have replaced a previous boss, or at least is the only boss to be renamed.
 * Ambulas is currently the highest leveled boss in the game, making it the "final boss".
 * Ambulas means "you walk" in Latin, fitting the boss's depiction as an upgraded MOA Walker.
 * According to Lotus after you kill it, the destruction of this Ambulas prototype has halted further production of this series of proxies, though it is unknown whether other Ambulas model proxies have already been built.