Nebula Gray

Nebula Gray (ネビュラグレイ) is a dark, monstrous program made entirely of Dark Power, created by Dr. Regal.

Game History
Nebula Gray is the final boss of Mega Man Battle Network 5. When Team ProtoMan/Team Colonel attack Nebula's HQ and deletes the Darkloids, the Darkloids in turn absorb them one by one into a dark vortex until MegaMan is the only one left. The Darkloids tell them that the vortex leads to the Dark Galaxy, a dark world created by Dr. Regal made entirely of darkness and Nebula Gray, a Dark Star at the center of the Dark Galaxy. After the team reaches and confronts Regal, they learn of his plan to taint the world with evil by linking the whole world’s souls by using SoulNet and then installing Nebula Gray into SoulServer to taint the world with evil.

MegaMan then jacks in into SoulServer and confronts Nebula Gray. At the end of SoulServer, he finds Nebula Gray to be a dark vortex with a blue flame hovering on top of it. Regal then explains that Nebula Gray is actually the digitized and amplified form of man’s evil soul. He then uploads that data into a system that converts it into various forms. He reveals that Dark Chips are made by grafting Nebula Gray's amplified evil souls into chip data, meaning that the human dark souls are the source of Dark Chips. Nebula Gray then transforms into a giant monster composed of a flaming head on a body of Dark Souls, having a vortex in the place of legs, and chains all over his chest and back. MegaMan then engages in a battle with Nebula Gray and wins.

However, dark souls return from inside the vortex and cover MegaMan, tainting him with evil. Lan takes off his MagnoMetal amulet to communicate with MegaMan’s soul using SoulNet, but fails. Then the voice of Lan’s grandfather comes out of nowhere and tells Lan that he’s always linked with MegaMan. MegaMan then transforms into his human form, Hub, and closes the vortex with Nebula Gray and locks him in a small metallic capsule.

However, the blue spirit of Nebula Gray returns and attacks a weakened MegaMan, only to have Colonel/ProtoMan save him by catching the spirit. MegaMan tries to shoot but is too exhausted, due to his attempt to lock Nebula Gray in the capsule. This takes a huge toll on MegaMan due to the amount of power that Nebula Gray had. So his friends and the rest of the Team come and lend him their power through SoulNet. With a powerful charged shot, he permanently destroys Nebula Gray, along with SoulServer. Regal’s memory is then erased by Dr. Wily and he then starts a new life as a law abiding scientist.

Within the Nebula Area resides the birthplace of the Darkloid King Chaos, also known as Chaos Lord. It can take on several forms; MegaMan’s Dark Soul, Bass.EXE, or Nebula Gray (although one can technically assume this is meant to be Bass).

Anime History
Nebula Gray doesn’t appear in any episode of the series, but appears in the Japanese-exclusive movie Rockman EXE: Program of Light and Dark, which takes place somewhere in the middle of Stream. His appearance here is similar to the one in the game, however, he moves a lot and concentrates more on physical attacks. The only major difference in his appearance is the blue spirit, which doesn't appear here.

After his defeat in Axess, Dr, Regal had been transformed into data and became stuck in the cyberworld. He then begins to apply a new evil plan of using the Tadashi Hikari program to activate the Spectrum program, which causes beams of light to shoot through the real world transforming everything they touch into data. Regal wants to transform the whole world into network data, and to assist him in his plan, he creates the monstorous program Nebula Gray. He even captures Bass, brainwashing and manipulating him to attack MegaMan. Colonel then interferes and Bass is returned to normal. When MegaMan is about to destroy the Tadashi Hikari program, Nebula Gray appears and absorbs it, while the NetNavis retreat. Lan, Chaud, and Raika infiltrate the Netopian military base where Regal resides. There they meet a man called Baryl, who turns out to be Colonel’s operator. MegaMan jacks in to stop Regal, while Bass also appears, intent on having his revenge on Regal. However, neither of them is any match for Nebula Gray, who defeats them both with ease. MegaMan and Bass then unite, creating BassCross MegaMan. He then completely obliterates Nebula Gray, resulting in Dr. Regal summoning a black hole in a desperate and suicidal attempt to destroy them all. Bass pushes MegaMan out of the black hole’s way as he gets sucked in himself. Bass then absorbs Nebula Gray’s power by himself, while Regal disappears, as the base crumbles.

Nebula Gray's silhouette appears during the confrontation between Bass and Slur in episode 51 of Stream, showing that Bass has indeed absorbed the power of Nebula Gray after the events of the Program of Light and Dark.

Forms
Like Duo, Nebula Gray is a final boss that has 4 versions. However, unlike Duo, these versions can all be fought on the same save file.


 * Nebula Gray (2000HP) can first be fought through the door way to the final battle at Nebula’s HQ. Once the player enters, they will watch a cutscene and then jack in. Saving or using the Party Battle System (Double Team DS) at this moment is not possible. This version can be fought repeatedly.


 * Nebula Gray α (2500HP) AKA the Chaos Lord can be found at the end of Nebula Area 6, once the player has defeated all the DS Navis. This version is actually the Chaos Lord taking on Nebula Gray's form. It can be fought only once.


 * Nebula Gray β (3000HP) AKA the Chaos Lord can be found in the same place as the previous version, after the player has defeated all the DS Navis with an average of less than 45 seconds each. Once again, this version is Chaos Lord taking on Nebula Gray's form. It can be fought repeatedly.


 * Nebula Gray Ω (Nebula Gray SP in Japan; 4000HP) can be fought in place of the first version, upon obtaining the 7 icons. Once this version has been made available, it is impossible to face the first version again, as the Ω version replaces the first. The blue spirit in this version cycles faster and takes less time to stop in place for an attack once in front of the large entity. The Ω version can be fought repeatedly and beating it signifies the completion of the game, with a special picture of MegaMan and his Teammates appearing at the end.

Attack
Nebula Gray is invincible. The only way to damage him is to attack the blue flame orbiting him. In the movie, he does not have all these weapons, but is much stronger than his game version, as he is seen to single handedly defeat MegaMan and Bass.

Also, due to the hand in the way, Nebula Gray's field is immune to Area Grab, and his weakpoint can only be hit by attacks that do not involve the ground.


 * Black Prominence: Nebula Gray constantly fires dark flames at MegaMan in a snake shape that is stopped by hole panels, and is a passive move of his that often fills the gaps in between his attacks. The flame only comes from in front of or behind MegaMan.
 * Grave Fire: Sends a raging dark flame that always targets Megaman's panel (through firing it out of his mouth), then flame towers with faint despair faces erupt after MegaMan in a continuous fashion. It's possible to move around in a circle to have the attack not hit, but using a mode where MegaMan moves extra fast may cause him to run into the tail end of the flame chase.
 * Dark Chip: A small dark soul flies forward and appears as a floating dark chip for a brief moment. It then summons Dark MegaMan.EXE to the field, who uses a random Dark Chip:
 * Dark Thunder: CORNER ENEMY WITH THUNDER.
 * Dark Meteor: METEOR SHOWER ON ENEMY.
 * Dark Lance: ATTACK ENEMY FROM BEHIND. (Guaranteed use if the player is in the back column.)
 * Dark Sword: USE LARGE SWORD AND SLICE. (Guaranteed use if the player is anywhere but the back column.)
 * Hellflame Serpent: Disappears into the portal and turns into a serpentine/draconian figure of himself and then rushes at MegaMan. If it doesn't connect, it hits depending where the player was standing, and the panels all around on a 3x3 grid are then broken. Disastrous if the center of the player's field is struck, especially without a bypass over broken panels.
 * Thousand Death Hands: Similar to his Hellflame Serpent, Nebula Gray disappears into the portal, only it releases several leeching hands that drain MegaMan’s HP and recover his own when they connect. The hands are fired in a similar fashion to Meteor, but their patterns are rather erratic while aiming around the player's general area, despite the projectile speed of said hands being rather a bit slow in comparison. Cannot be avoided with a shield such as Life Aura or Bubble Wrap, as it will completely remove barriers of any sort if any of the hands happen to connect.

Trivia

 * Nebula Gray is the first final boss in Mega Man history that the player can battle without first dealing with a sub-boss.
 * As the personification of all the sorrow and hatred of humans and NetNavis, Yūji Ishihara notes in Mega Man Battle Network Official Complete Works that he made Nebula Gray out of roiling smoke that looks like fur. The white lines on his face represent all of the heavy emotions pouring out. The chains represent Regal's control over him.