When the beast is complete, its dark arms shall encompass the planet, ushering in the end of times. The world, in death, will fall into a deep sleep in waiting for the time of rebirth to come.
— Gaia Manuscripts, 4:28, Sonic Unleashed
Perfect Dark Gaia (パーフェクトダークガイア Pāfekuto Dāku Gaia?) is the final boss of Sonic Unleashed. It is the completed form of Dark Gaia, achieved when the beast reaches full maturity for the time of awakening, making this form the representation of Dark Gaia's true nature as a deity of darkness and destruction.
Basically, Perfect Dark Gaia resembles its immature form, but with extra features. Once matured, it grows four extra arms and its large mouth opens up, revealing hundreds of tongues which give way to seven aligned green eyes; three smaller ones on the sides and one large in the middle. It also gains two long tongues hanging out from each side of its central eye. Its seven tentacles (seen only in the Xbox 360/PlayStation 3 version) also move down its spine and their ends gain more shape, resembling snakeheads with smalls Mohawks and a green eye in their mouth.
Every few millions of years since the beginning of time, Dark Gaia has assumed this form when emerging during the time of awakening to destroy the earth, only to engage Light Gaia. At the end, Light Gaia defeats Perfect Dark Gaia and seals it and himself in the planet's core where they rest until their next battle.
In Sonic Unleashed, when the world was broken apart by Dr. Eggman's Chaos Energy Cannon, Dark Gaia was interrupted during its maturing process due to its premature awakening. As such, its power scattered across the broken planet when it tried to emerge. However, Dr. Eggman devised a way to summon the fragments to Eggmanland and harness it as a fuel source. Eventually, Eggman collected enough energy for Dark Gaia to assume an incomplete physical form and emerge in the planet's core. Absorbing the remaining part of its power from Sonic the Werehog, Dark Gaia would regain its full power during its fight with Sonic and the Gaia Colossus and mature into Perfect Dark Gaia after casting the planet into darkness. Before it could utterly destroy the planet though, Dark Gaia was forced to fight the combined forces of Super Sonic and the Gaia Colossus. After an epic battle, Perfect Dark Gaia was defeated and sealed in the planet's core again until its next awakening.
Powers and abilities
Perfect Dark Gaia wields the same abilities as its premature form, but at the peak of its strength and capabilities due to having regained its full power. In this state, Perfect Dark Gaia is one of the most powerful beings in the series, being able to injure a Super State through the brute force of its attacks. It could as well occasionally overpower its equal, Light Gaia, while taking on Super Sonic at the same time and wear him down to the point where he fainted from exhaustion.
Having reached full maturity, Perfect Dark Gaia's immense super strength and endurance have increased further. It is capable of completely immobilizing the Gaia Colossus in its grip and even overpower him in extended hand-to-hand combat. It can also channel extremely powerful energies into a more extensive variety of attacks than before; it can shoot large beams from its central eye without losing focus should the process be interrupted (unlike its premature form), project purple orbs, launch black orbs with paralyzing effects, and channel its energies into its claws for enhanced slashes.
Through its snake-like tentacles, Perfect Dark Gaia can generate a force-field around itself that not even Super Sonic could penetrate. Furthermore, Perfect Dark Gaia has gained vast telekinetic powers that let it pick up enormous balls of magma without touching them and throw them as meteors. Like its premature form, Perfect Dark Gaia also has enough heat resistance to be submerged in magma without getting burned.
Perfect Dark Gaia's weak points remains its various green eyes, like its earlier form, which are highly sensitive to damage. It is also not immune to its own power, meaning it will take damage from its own energy attacks should they be knocked back.
For this battle, the player controls Super Sonic as he flies in front of Perfect Dark Gaia. During the battle, the player can utilize the Turbo Boost to dash around on the screen and Deflect to throw the monster's projectiles back at him. Unlike most boss battles in the Sonic series, Super Sonic will lose ten Rings when hit by Perfect Dark Gaia's attacks. To defeat this boss, the player must collect Rings that float around to charge the Boost Gauge enough to use the Super Sonic Boost and hit each of Perfect Dark Gaia's eyes once. For every tenth Ring in the player's possession, the player can use the Super Sonic Boost once, but using it will also derive Super Sonic of ten Rings. At the same time, Super Sonic will use up one Ring per second, and losing all Rings will cost the player a life.
This battle is lengthy and tough. While collecting Rings, the player must move in the direction of Perfect Dark Gaia's still-open eyes, and when in front of one, a red target reticle will appear, indicating an opening. Such an opening also occurs when Perfect Dark Gaia roars. Upon launching the Super Sonic Boost at an eye, the player controls Super Sonic as he flies towards it. If the attack successful connects, the player wounds the eye and starts the process over again. With each eye though, meteors start appearing during the attack on the eye. Try to anticipate their trajectory and maneuver accordingly. If hit, Super Sonic will not lose Rings, but his attack gets canceled.
During the battle, Perfect Dark Gaia will attack mainly with its claws. As the beast cocks its arm back, a faint slash ﬂashes onscreen, illustrating where the attack will land. The faint slash is followed quickly by the actual attack, so move quickly to avoid it. As the player attacks more of Perfect Dark Gaia's eyes, it will slash faster and use all its six claws simultaneously. Quickly move to the screen's center to avoid the latter attack. Eventually, Perfect Dark Gaia will also start firing energy projectiles at Super Sonic. Follow the onscreen button press at just the right moment to deflect the shot back at the source. This will temporarily stun Dark Gaia, allowing the player to collect rings and target its remaining eyes. After hitting six eyes, Perfect Dark Gaia will reveal its central and much larger eye. After hitting this eye, Dark Gaia is finally defeated.
The time needed to "S" Rank is a total time of 7:30 between this boss and the previous one. Failure to make that time will yield a "C" Rank. Therefore, no Sun Medal will be awarded.
Xbox 360/PlayStation 3
Perfect Dark Gaia is the overall eleventh and final boss of Sonic Unleashed. It is fought with Super Sonic directly after defeating Dark Gaia. The battle has Super Sonic take down the tentacles of Perfect Dark Gaia before engaging in a series of Real-Time Interactions.
The battle with Perfect Dark Gaia is fought in multiple phases. Here, the player controls Super Sonic whose only usable move is the Super Sonic Boost, while playing as the Gaia Colossus during Real-Time Interactions. Unlike other boss battles in the Sonic series, Super Sonic has a life gauge instead of a Ring count, which is increased when gathering Rings and depletes when Super Sonic is hit by floating rocks or Perfect Dark Gaia's attacks. If Super Sonic's life gauge is emptied, the player will lose a life.
In the beginning, Perfect Dark Gaia sets up an shield that Super Sonic cannot break. The players begin by charging towards Perfect Dark Gaia while dodging rocks and energy orbs. It is also important to gather up as many Rings as possible here to increase Sonic's life gauge, as there will be no other Rings available upon reaching Perfect Dark Gaia. After dodging the rocks, Super Sonic and Chip (as the Gaia Colossus) will reach the shield. Chip goes through the shield and distracts Perfect Dark Gaia, while Super Sonic must destroy the source of the shield, which appear in the form of serpent heads that extend outside it. These heads can be destroyed by boosting into them repeatedly, but the player must watch out for nearby rocks, which will make Super Sonic take damage. Chip has a life gauge as well, so the shield must be destroyed before Chip's life gauge is depleted or they lose a life. Sometimes, Chip goes down and Perfect Dark Gaia starts to attack Super Sonic through the force field. Here, it mainly attacks with a large laser or by using what appears to be telekinesis to send out flaming rocks at Super Sonic. Chip will eventually rise though and distract Perfect Dark Gaia again for the player.
Once the shield is down, the player enters a cinematic gameplay section. Here, Perfect Dark Gaia grabs Chip with its six arms and starts charging its laser. Super Sonic goes in to save Chip by boosting into all six arms, which is done in gameplay by completing a button-pressing Real-Time Interaction (, , , , , /, , , , , ). After that, Chip is freed and leaves Perfect Dark Gaia in agony, but it has still charged enough to shoot its laser at Chip. Chip takes heavy damage from the laser, but withstands (which is done in gameplay by pressing / sixty times within ten seconds). After negating it, Chip punches Perfect Dark Gaia. Super Sonic then comes in, and the player will have two options; either finishing Perfect Dark Gaia by boosting through its middle eye, or let Super Sonic gets it automatically. The boss ends immediately after that.
To achieve an S-Rank, the player has to just avoid hitting any of the floating rocks and evade Perfect Dark Gaia's attacks. Losing a life in this battle or the player's performance in the previous battle against Dark Gaia do not affect the player's Rank.
In other media
In the Sonic the Hedgehog comic series and its spin-offs published by the Archie Comics, Perfect Dark Gaia appeared in at the end of the Shattered World Crisis story arc. Like in Sonic Unleashed, Dark Gaia achieved this form after regaining its full power, where it was defeated by both Super Sonic and the Gaia Colossus.
- Perfect Dark Gaia is one of the two characters with the "perfect" prefix in their names, the other being Perfect Chaos. Both of these characters are final bosses.
- At the beginning of the Xbox 360/PlayStation 3 version, the fight against Perfect Dark Gaia is similar to Sonic & Knuckles' The Doomsday Zone (avoiding asteroids and collecting rings). However in this game, crashing into an asteroid deals light damage to Super Sonic, while in Sonic & Knuckles it only slows him.
- The lava during the boss fight is noticeably brighter in-game, while in the cutscenes it seems to be darker and gives off less light.
- In the Wii/PlayStation 2 version of the game, Perfect Dark Gaia's eyes are shown to have vibrant green eyelids, which close one at a time whenever one of the eyes is attacked. The eyelid on the central eye however, will not open until the other six are attacked. It is also worth noting that these eyelids are not visible in cutscenes.
- Perfect Dark Gaia's in-game render shows him to have a slightly thinner head and larger eyes than his model in the CGI cutscenes.
- Looking closely right after Dark Gaia transforms, one will notice that only his central eye is staring at the Gaia Colossus while the others are all facing in different directions. This is also seen during the fight in the Wii/PlayStation 2 version of the game, in which the individual eyes can be seen shifting around and never looking directly at Sonic as he approaches them.
- In the Xbox 360/PlayStation 3 versions, when Super Sonic finishes off Dark Gaia, Sonic's flight path makes him clip through its second hand's thumbnail, an oddity for a pre-determined game scene.
- Sonic Team (18 November 2008). Sonic Unleashed. Wii. Sega. Cutscene: A World Clad in Darkness. "Professor Pickle: Dark Gaia has regained its true power. The beast is complete. It's just as the Gaia Manuscripts foretold. "And the world shall be plunged into the dark of night, the dark of destruction." Oh, that it should come to this! We're doomed. The planet is lost!"