Sonic & Knuckles
The Doomsday Zone is the eighth and final overall Zone of Sonic & Knuckles (and the fourteenth and final Zone of Sonic the Hedgehog 3 & Knuckles). Under normal circumstances, this Zone is only playable as Sonic, but it is playable with Tails or Knuckles from Level Select/Sound Test if Debug Mode is enabled. Sonic must have all seven of the Chaos Emeralds to play the zone as Super Sonic; if the seven Super Emeralds are also obtained, the player can also play the level as Hyper Sonic (Sonic the Hedgehog 3 & Knuckles only).
The Doomsday Zone is set in a region of outer space high above Earth, with clusters of asteroids scattered all around. The elapsed time of the battle takes place in this extensive field of asteroids.
The Death Egg has once again been destroyed from Sonic's victory over Robotnik in the Death Egg Zone, but the Master Emerald remains in space. Now, as only Sonic and Robotnik remain in a race against each other, Sonic must summon the power of the Chaos/Super Emeralds to neutralize the evil scientist for good.
Sonic automatically gains 50 Rings at the battle's start and instantly transforms into Super Sonic/Hyper Sonic (the latter's case is if all seven Super Emeralds are acquired). Because of his Super/Hyper Form, Sonic's rings are steadily depleted (by one ring every second), so he must keep picking up rings scattered around during the fight in order to keep his Super/Hyper Form. He must also be wary of asteroids, which slow him down to a near halt if hit, and missiles which render him unable to move or collect Rings for some time. Although only one or two hits are unlikely to jeopardize the player's chance of success, even a slight lack of concentration can cause Sonic to collide with many obstacles and get pushed dangerously far behind. The , , or buttons will make Sonic fly faster in any direction. If Sonic's rings deplete all the way to zero, he will lose his Super/Hyper Form, fall off the screen, and immediately die.
The first section of this level prompts Sonic to dodge an onslaught of missiles in a slalom-like fashion, and Sonic must stay between the pairs of missiles (or avoid them completely) as they move up and down. Rings occasionally show up in groups of 3 or 6, buying Sonic valuable time if any are collected, although of 8 to 12 may appear at the top and the bottom of the level. This makes it possible to gain 100 or more rings (and a 1-Up) in the first part of the stage before reaching Robotnik's ship.
The ship, a large blue destroyer-like spacecraft, has a launcher on the bottom which fires homing missiles at Sonic, and has a trio of cannons on its side which constantly fire unguided bullets. Neither of these will cause Sonic harm, but will temporarily immobilize him, hindering his efforts to destroy the ship. The ship is completely impervious to any direct attacks by Super/Hyper Sonic so, he must guide the homing missiles into its head while avoiding the heavy ammunition it shoots. This must be done quickly, as rings cannot be collected during this part of the fight. Once the ship has sustained eight rockets to the head, it will burst into flames and fall off-screen before exploding, initiating the final phase of the boss.
A giant red humanoid-like robot with a jetpack emerges out of the blue outer shell, clearly carrying the Master Emerald in its hands. It resembles the Death Egg Robot in design (possibly rebuilt after its previous destruction), but with a more streamlined appearance and features similar to those of an EggRobo. It releases bombs if overtaken from above, and spiked mines if approached from below. Sonic must catch up to it and touch its head eight times to destroy it and recover the Master Emerald. This task should be done quickly, as Sonic may have trouble regaining rings faster than he loses them, especially while avoiding another wave of asteroids.
What is interesting to note is that, within Hidden Palace Zone (three Zones previously), a mural in the background during the battle between Sonic (and/or Tails) and Knuckles depicts an abstract version of this battle.
- This level marks the first time in a recurring succession of Sonic games that the final level uses a Super form setting in a race against time and depleting Rings, only accessible through obtaining all the Emeralds.
- The music for this Zone is also used in Knuckles' version of the Sky Sanctuary Zone during the final battle against Mecha Sonic's Super State.
- A remix of the music that plays in this Zone was originally supposed to be in the Nintendo 3DS version of Sonic Generations for the boss fight against Big Arm, but it was later replaced by a remix of the final boss theme of Sonic the Hedgehog 3 & Knuckles.
- In most versions of the game, the music will accelerate in tempo when Sonic runs dangerously short of rings (10 Rings or below), increasing tension in the player and urgency to keep collecting Rings. This is similar to the Special Stages after some time has passed. This is missing in Sonic Jam.
- After Knuckles finishes this Zone in debug mode, he is seen blue on the Tornado and the original red one will be watching him at the end. He is also seen with two Master Emeralds, one in his hand and one on the back of the tornado.
- The final form of the boss appears in Sonic and the Black Knight in winning fanart.
- A variant of the boss appears as the final boss of Sonic the Hedgehog Pocket Adventure in the Chaotic Space Zone.
- The music for this Zone was remixed as the music that plays during the battle against Mecha Sonic at Aerobase Zone in Sonic the Hedgehog Pocket Adventure.
- There is technically an unused "Act 2" for this Zone, but it can only be entered through a glitch or hacking. The Act is just a black screen with Sonic turning into Super/Hyper Sonic, but immediately falling to his death to having 0 rings.
- If the player accesses this Zone using Level Select and completes it they will get the bad ending.
|The Doomsday Zone||Tatsuyuki Maeda, Tomonori Sawada, Sachio Ogawa, Masayuki Nagao, Masanori Hikichi||2:01|
|The Doomsday (FM Synthesizer)||1:54|
|The Doomsday (General MIDI)||1:51|