The Emperor Ing is a boss from Metroid Prime 2: Echoes. It is the eldest and most powerful Ing in the Horde. It resides in the Sanctum within the Sky Temple, guarding its Energy Controller, from which it siphons energy. Like other Ing, it is a metamorph, and Samus battles it in multiple forms. When defeated, Samus takes the last of Dark Aether's planetary energy, initiating a Countdown to Dark Aether's destruction.
The Emperor Ing's first form is stationary, with tentacles protruding from its head. In this form, it uses several melee attacks with its tentacles. It also fires bursts of Dark Energy, but these can be easily dodged in Morph Ball form. Samus can damage the tentacles with a variety of weapons.
Once each tentacle is destroyed, the head will retract, revealing its eye. In this form it fires a sustained energy beam that travels slowly and has limited range near its body; these crimson beams are quite potent and will impede Samus's ability to aim briefly if they make contact. The eye is covered with a rotating shield that is impervious to weapons, but that has two vulnerable gaps on a single axis that Samus can fire through.
After enough damage has been dealt to the eye, the head returns and generates more tentacles than before. It continues to use its melee attacks and the Dark Energy attack, but it gains two new attacks: it will now pound on the ground with its tentacles, leaving them quite vulnerable to Power Bombs, and will begin using transdimensional teleportation to send its tentacles throughout the room in an attempt to attack Samus.
The cycle repeats until the eye has been seriously damaged, beginning the next phase.
Emperor Ing Chrysalis
After it has taken enough damage to its eye, the Emperor Ing's head swallows the body, forming a nearly impervious regenerative shell in which to shield itself while it heals. Poisonous gas fills the room, but the shell is magnetically charged, allowing Samus to cling to the shell using her Spider Ball.
The shell has 11 weak points on its surface that can be damaged with Morph Ball weaponry. The Emperor Ing will generate tentacles in these weak points if Samus comes near to knock her away. Samus can either drop Morph Ball Bombs near the tentacles to destroy them or use Power Bombs to destroy multiple tentacles at once.
Inglets appear during this phase, allowing Samus to regain health easily by destroying them. After all weak points are damaged, the Emperor Ing emerges from its shell and the next phase begins.
Mutated Emperor Ing
After the shell is destroyed, the Emperor Ing, now further mutated by Phazon, will emerge in a form similar in appearance to a Warrior Ing. Like Warrior Ing, it can fire transdimensional energy beams, but unlike them, it can fire multiple beams simultaneously. It is also capable of firing a sustained blast of light or dark energy, with Lightblast- and Entangler-like effects. It uses physical attacks, such as ramming and jumping at Samus, but also attacks by creating swarms of Nightbarbs or of an unnamed flying white creature.
In this form, the Emperor Ing's vulnerable core can render itself impervious to certain types of energy. In its neutral state, the core can be weakened by Samus's full arsenal of Arm Cannon weaponry, including beam, concussion, and combination weapons. Once it has been sufficiently weakened, the core will erect a barrier that can only be damaged by a beam of opposite polarity or the Annihilator Beam, indicated by a change in the color of the core. After a long and grueling battle, Samus defeats the mutated monstrosity and claims the last of Dark Aether's energy.
The Logbook data for the Mutated Emperor Ing suggests that there would be energy barriers around multiple weak points. However, there is no such behavior in the final release of the game. Other indications that the battle was originally more complex include official artwork that shows the the Emperor Ing's leg joints filled with orange orbs, an untextured model stored with the Emperor Ing's graphics that would've fit perfectly into those leg joints, and an interesting glitch in which the Screw Attack deals damage when it contacts those joints.
- "Bioscans indicate that this is the eldest, strongest Ing in the Horde, the alpha and the omega. It has absorbed enormous amounts of Phazon energy into its body, mutating itself in the process. Apparently this power is not enough for the creature, as it is now siphoning energy from the final Energy Controller." —Metroid Prime 2: Echoes Logbook "Emperor Ing Body" (Metroid Prime 2: Echoes)
- "Like its brethren, the Emperor Ing is a metamorph. It has molded itself around the precious Energy Controller, and will defend it to the death, using its own body as a shield and weapon. Destroy the tentacles it generates to weaken the creature and its defenses." —Metroid Prime 2: Echoes Logbook "Emperor Ing Head" (Metroid Prime 2: Echoes)
- "The Emperor Ing has exposed its main eye, from which it can fire powerful energy beams. It is protected by an energy shield, although not completely. The eye can be locked onto, but only direct shots will get past the shield." —Metroid Prime 2: Echoes Logbook "Emperor Ing Eye" (Metroid Prime 2: Echoes)
- "The heavily damaged Emperor Ing has entered a regenerative state inside a durable healing shell. Tactical scans have detected eleven weak points on the magnetically charged shell: Spider Ball travel is possible on the shell surface. Damage the weak spots with explosives to crack the shell and expose the enemy within." —Metroid Prime 2: Echoes Logbook "Emperor Ing Chrysalis" (Metroid Prime 2: Echoes)
- "Further exposure to Phazon has mutated the Emperor Ing. It is now capable of shielding its vulnerable areas with energy barriers. Beams of opposite polarity can damage these barriers, however. Heavy damage to these barriers will cause them to drop, exposing the creatures weak spots. Target the weak spots to immobilize and damage the enemy." —Metroid Prime 2: Echoes Logbook "Mutated Emperor Ing" (Metroid Prime 2: Echoes)
- The Cutting Room Floor