Submitted by: Scott Prower

Inside the Red Hot Skull section of Red Mountain, the lighting was a lot harsher in the preview build. Sonic is almost pitch black. Also, that area to the left is meant to be filled with Lava.

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Submitted by: Scott Prower

Sonic barely misses an exploding rock. In the final a similar situation occurs where Sonic gets flung to the other side of a canyon, but the dust is more white, and Sonic plays a different animation to what he is in this image.

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Submitted by: Scott Prower

In the final version, this same section has very different floor textures, almost light brown. Here they're dark with black splotches.

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Submitted by: Scott Prower

Again, Sonic is affected by the harsh lighting of the level. in the final, rgardless of where he is, Sonic is obviously blue, unliek this very black colour he is here.

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Submitted by: Scott Prower

Again, harsh lighting.

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Submitted by: Rlan

From the video, you can tell that this button is a lot different to the final. It's green, while in the final it uses the bumper star design.

Submitted by: Rlan

The launching platform is also very different, a lot bigger than the ones from the final.

Submitted by: Rlan

All of the black areas in this section are usually filled with a cloud background which is constantly moving. Here it's missing.

Submitted by: Rlan

In the video the camera does a large swoop of the area. Although probably just for effect on the video, this doesn't happen in the final.

Submitted by: Rlan

A good shot as to what the background looked like. The sky is entierly blue, but in the final it's filled with clouds.

Submitted by: Rlan

Sonic is homing attacking a whole section of enemy robots, but his homing attack isn't attacking very well. His movement is sort of circular as his movement bends downwards. In the final Sonic will dash directly to them.

Submitted by: Rlan

Gamma slowly locks onto all of the enemys surrounding him, but no numbers are popping up next to them.

Submitted by: Rlan

Knuckles is standing around an area of Red Mountain, but this bridge does not occur in his part of Red Mountain, only Sonics.

Submitted by: Rlan

Showing thr drastic changes in the background is this image, although still far from complete. In the final those far away rocky hills are moved upwards, and no black area can be seen.

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Submitted by: Rlan

A few seconds after, Sonic begins to slide down to an area below.

Submitted by: Rlan

Sonic's jut about to grab another ring. The red bridge is just ahead, and the background is radically different.

Submitted by: Scott Prower

A little further up, and there is no badnik present when there should be.

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Submitted by: Scott Prower

Although similar to the final, the camera is in a weird position.

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Submitted by: Rlan

Sonic jumps through the cracks of the Red Hot Skull area, with the different lighting.

Submitted by: Rlan

Sonic giving the camera a grim look with an animation we don't see in the final. This image also gives us a good look at the lighting effects at the time.

Submitted by: Bartman

In some of the early videos, the HUD displayed the word 'Level' along with the time and rings. It's not used in this revision, and is deleted in the final. Also, the Ring in the rings counter is larger than the final version.

Submitted by: T2TheFox, Ice Dragon

Long thought to be an unknown area, the mystery of the top screenshot was solved by Tim, who realised that the speed-up half pipe is in the background, which is in Red Mountain.

Thanks to Tim's spot [and digital camera], Using SADX, Ice Dragon took a picture of the area. Clearly, the Spiked Balls were not implemented at the time, so it looked bear and like an area of the Mystic Ruins in the top shot.