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This is the last zone in the current (demo, mind you) version of SRB2, although it is slated for Zone 4 in the final version. It has enemies abound and level design that leaves you unable to remember where crucial points actually are, or at least unable to remember how to get to them.

[edit] Act 1

This level is along the lines of Techno Hill Zone 2, but more focused on the finding of the switch. A short run takes you to a area with a wall, a pond, a bridge, and a massive cliff. As Knuckles you can climb up the cliff, but it's too far for Tails to fly. A underwater cavern in the back left of the pond takes you to the cliff top fast, with a drowning risk. From then on, it's tunnel trial and error time until you get to the stone octagon-shaped switch. Once you have hit it, go back to the bridge on the pond, and you will see that the door in the wall has opened and revealed the exit, a la THZ2.

[edit] Act 2

A first look at this level makes it seem easy. There is one thing you won't find: the exit. What you have to do is find the numerous switches scattered around the level to open the Eggman walls that bar the exit. Yes, there is a Special Stage token in this level, it is in the back part of the water pool behind the castle wall, behind some short walls.

[edit] Act 3

• Boss: Spike Eggmobile
• Hits to Defeat: 8

This is it. The final level. The boss here is little more than a version of the GFZ boss with a spike ring. However, that one spike ring makes the boss exponentially harder, plus the threat of Death by Jetty-Syn. The boss acts exactly the same as the Eggmobile from GFZ. 8 hits and it's all over. There isn't even a capsule like in the early levels. Roll the credits... but this is not the end. Far from it.