Death Egg Zone (S&K)
From Sonic Retro
Death Egg Zone is the seventh level in Sonic & Knuckles. As the name implies, the stage is set in the enormous hull of the Death Egg. There are gravity changing devices, high-speed transport tubes, and even an engine room with buttons that must be turned to the same color in order to exit the room. Sonic enters by jumping on board from Sky Sanctuary, and exits for a final battle with Robotnik in space as the Death Egg falls apart.
Knuckles doesn't participate in this level as Sky Sanctuary concluded his story, however using Level Select he can play this stage normally...for the most part. He's unable to beat the first boss due to his lower jump height.
Bosses and Strategy
The bosses, as to be expected, are difficult.
The Act 1 boss is a giant eye with rotating balls around its center. You have to wait for the balls to spin outward then get in the center. Jump up to hit the eye and at the height of your jump, hit jump again. You'll hit it. Damage it eight times and the eye will separate from its metal base. At this point, get on the platforms spinning around it and attack the center until the platforms begin orbiting the eye quickly. Then get away and watch for the laser coming from the bottom. Hit another eight times to win.
The first one of the Act 2 bosses is self-defeating, as long as you know what you're doing (which is to say that it provides you your ammo and can't be attacked directly). It is a floating ball that resembles the Death Egg. It drops crawling bombs. When you have one almost lined up, go into the teleporter and gravity will switch, causing the bombs to hit the boss. Do this eight times to win. You can also flip the bombs with a Spin Dash if they are stuck point-first in the ceiling or floor, making for a much faster fight.
The following boss, considered the normal final boss of the game: a massive robot similar somewhat to that in the Sonic 2 version of Death Egg Zone (only bigger), that is listed in the level select as "Doomsday Zone 2", but is actually part of Death Egg. This boss has three phases: the first phase is merely smashing his fingers, in other words, the robot will try and smash you with its hands. You must destroy all of its 6 fingers to get past. The next part is a bit more difficult, as the robot will destroy any floor it touches, so you have to run through the whole thing. The robot is behind you; you'll just have to jump on an exact point of the robot (the place where he shoots fire from) and it will open up its shell and use the Master Emerald to fire a beam at you. The beam can be avoided by jumping right before it is fired, i.e. when the sound effect ends. After or before the beam is fired, you have to jump and hit the container holding the Master Emerald. The bot is still moving, and the container will close quickly, so you have to be fast. It takes 8 hits to finish this second phase. Finally, after that, Eggman will quickly get in his little pod and carry the Master Emerald away. You must hit him 8 more times; afterward, he will drop the Emerald and you will have beaten him!
Instruction Manual Description
Sonic Team Commentary (from Sonic Jam Strategy Guide)