Surprisingly, the Death Egg is actually rather hollow on the inside. Act 1 is based entirely within, and you can see the massive far inner wall of the 'Egg in the background, so it appears to be set inside this huge, hollow space, making for a massive and open mechanical arena. The wall gets darker as it leads in towards the centre of the screen, to shown the curvature of this spherical behemoth, and there's a seal along the middle where the two halves of the shell join. Most notable however, is the long blue vertical core in the centre, cylindrical and segmented. This and the walls are filled with tiny flashing lights and almost alien-esque architectural detail. In fact, it almost resembles the inside of an alien mothership of some form. This small piece of background occupies the screen only, so there aren't really any high or low areas to see, based on where you are in the level. The same goes for Act 2 which, by contrast, is set entirely outside the Death Egg, in space, on some of its external platforms. Here, the background is basically a large portion of the planet below (whatever particular planet you may consider that to be), which goes across most of the screen, curving slightly at the top, and leaving some black emptiness in the space above. It looks rather dull coloured, with dark greenish ocean and grey clouds.

The foreground remains consistent through both acts and is fairly detailed. The roads and ceilings are pathed with thin vertical lines, alternating between shiny silver bars and black spaces of an equal width. The ground beneath is often buzzing with activity, full of small cogs and generators vibrating very quickly and glowing from one shade of bronze to another. All this gubbins is segmented into a grid of large square windows across the whole board, made up of strips of bolted down metal to form the edges of the squares, and sometimes diagonal pieces to go across. Once again, Eggman goes for the more old-fashioned clockwork method of cog systems and so forth to help power his mighty machine of death. It looks considerably more advanced than the design of Metropolis Zone though, for example. The large white chunks of cylindrical transport tubing are made up of a series of white shutters, with the word "EGG" printed on them at the tops and bottoms, and the conveyor belt/elevator sequences are controlled by a large, thin spiralling contraption going down the centre.

Unlike the original Death Egg Zone in Sonic 2, which was no more than a small arena for the game's final battle, this Death Egg is most certainly a proper zone, with two massive acts and all the trimmings. The structure, save for a few large areas for platform hopping and twisting, twirling light beam transportation, is very much an enclosed affair with corridors and rooms, and ceilings of varying heights, and the layouts are fairly long and complex. Most pathways are straight, with only gentle slopes here and there, though you'll also regularly find large pits, sometimes fairly deep ones, along the path. Falling in them is usually more of a setback than it is helpful, though they don't always contain harmful objects in them. Some have curved bottoms, so that you can spin dash back up, while for others, you may need to go back through an exit, and try again, without falling in. There are only a couple of bottomless pits where you'll die instantly (Points #4 and #8), but beware of them anyway. Use various platforms to cross dangerous electrical fields and open gaps, and there are several sections where you need to use a long moving conveyor belt platform to go up or down a wide vertical shaft, avoiding the obstacles along the way. Not a particularly fast zone, as the design is more based on forcing you to negotiate through the many obstacles, though there are some small bursts here and there, sometimes thanks to the speedy transportation systems.

Death Egg's obstacles are a noisy bunch, each emitting their own spacey sound. Over wide gaps, there's often a very thin blue light beam bridge going across, emitting high pitched noises. This bridge is safe to run on, but do so very quickly, because it disappears and reappears at very regular intervals, and if you don't make it, you'll usually fall down one of the many bottomed pits in this stage. The small black gravity ball that swings around a white checkered box won't hurt you, but will reduce the gravity a bit, so that you float over it when you pass by. Large green-ish platforms with a red horizontal stripe sit stationary in the air. Jump at the bottom of one and you'll be able to grab onto it, at which point it floats upwards and across to another section, usually over an electricity field, and you can jump down safely at the end. These dangerous orange electricity fields can be found on floors and ceilings and are harmful to touch at all, unless you have the lightning shield, which will allow you to walk along them safely. You still need to be careful though because some of them produce bolts of lightning that jump out a fair distance, which your shield cannot protect you from. In fact, when there's one of these on the ceiling, it's usually best to avoid jumping at all while walking under it, otherwise a bolt may reach out and hit you at that distance.

Blue and orange balancing platform blocks, arranged in horizontal strings can be tricky, and feature in both acts. They begin stable, in a neat line but are very responsive to the weight you place on them. When you step on them, they'll begin to tilt in favour of the end you're standing on, so that landing on the left side will cause the blocks on the left to drop, while the ones on the right will rise up, and the further you are to the edge, the more severe the tilt. Even though you don't need to, you can jump over to the right ones to try and restore the balance, but getting them back in a straight line seems to be more or less impossible. When they reach a far enough tilt in either direction, they'll all just drop down, and at one point in Act 2, you'll fall to your death if you stay on them. In most instances, you'll come in from the left and need to use the platforms to get up to a higher ledge on the far right. Jump on the left side to get the tilt going in your favour, and then head on over to the right when they begin to tilt a reasonable distance, so that you don't accidently re-balance them when you get over there. Hopefully, the tilt will push the far right block up high enough that you can make it to the next ledge, but you may need to be careful of further hazards, such as a missile shooter in the wall, nearby.

Small turquoise platforms on long swinging arms made of a string of small spheres will swing up or down by 90 degrees when you step on them, similar to platforms from Sandopolis. Each will only go in one particular direction, and it'll return to its original state as soon as you leave it. Meanwhile, reminiscent of Star Light Zone, groups of four staircase blocks arranged horizontally will move up or down when you stand on them to form their steps. While Star Light also had balls of flame coming out of the walls in these sections, Death Egg has small missiles here, and in many other places too. They're lined up in groups on either wall of a long vertical passage, where you need to use the steps to get up, and you can tell when one missile is about to be fired when it pokes its head out of the hole. When you find a red barricade blocking a doorway, it usually means that the route is one-way only, so if it opens when you get near, it'll seal behind you when you step through, so there'll be no turning back. These are commonly found either end of large white tunnel tube systems, which Sonic will run around inside, similar to the rotating cylinders earlier on in Flying Battery. These ones, however, are made up of a number of segments of varying sizes, and you'll need to use the right and left buttons to travel through the winding paths they create. Use speed-up devices on the ground to get those legs moving instantly in one particular direction, and there are conveyor belts across some areas of the ground, though theses ones make little difference to anything really.

Very influential though are a number of conveyor belt elevator sequences throughout the stage. They're fairly self explanatory, but you can easily lose lives on them without enough rings to hand, and there are two different types. The first is a long conveyor belt platform that spans the whole width of the vertical shaft they're in. Step on it to get it to start moving up or down, but beware of spikes on the side walls, as the conveyor belt will continually force you into them, so you'll need to be on the move all the time. If you're in the wrong place at the wrong time, you can get crushed into the sides of them too. The main annoyance in these sections are the missiles that fire from the walls while you're on the way, and there are electricity fields at the top and bottom of the shaft. Top tip for the missiles: They won't fire from the opposite wall if you try and hold your position on one side of the conveyor belt, so as long as you try to keep the opposite wall off of the screen, no missiles will be fired from it. Otherwise they can be damn hard to dodge. You can also reverse the direction of the conveyor simply by jumping. When you land, it'll force you in the opposite direction. In Act 2, you may also have to tackle these things upside down. The second type is a smaller conveyor belt platform that only fills half of the shaft's width, and while the bottom of it treads along, the top part is perfectly stable to stand on. It bounces from side to side of the shaft as it goes down, and there are only missile shooters on the sides of the walls for this one. The key difference is that it actually continues to move along on top of a series of electricity fields at the bottom, bouncing off of walls and dropping down gaps in the floor to take you safely along to the next area. The fields don't spout dangerous electricity sparks here, so if you have the lightning shield, you can run along them safely, yourself. Not that you really need to at all, but you can also change the direction of these as well, by jumping, and landing back on. There's one of these in each act.

At the half way point and towards the end of Act 1, you'll find a really wacky light beam transportation system. Simply stand just in front of a turquoise post with a small screen on top and two wheels will get you spinning, building up speed, while the screen begins counting down; 3, 2, 1. At 0, Sonic blasts off inside a kind of snake made up entirely of circles of yellow light. This "light snake" twists and turns madly over a huge open room, going through a bizarre, looping route all the way around before finally taking you to the next ledge and throwing you along with speed. In Act 2, the reverse gravity system will kick in, moving Sonic back and forth from the ceiling to the floor, and there's more than one object that you can use to change the gravitational direction. First of all, long vertical tubes have a right side up entrance/exit at the bottom, and an upside down one at the top, usually. Step inside one of the entrances to start spinning around increasingly quickly, and then get zapped up or down to the other end, where you'll find yourself in the opposite gravitational pull. You can also press on a blue button to flip yourself around the other way, and small patches of the white tunnel tubing will do the job too. Act 2 also adds simple grey and blue moving platforms that hopefully by this point require little explanation!