Lost Labyrinth Zone is the third level in Sonic the Hedgehog 4: Episode I. It appears to be set underground, similar to Sonic 1's Labyrinth Zone, and draws similar comparisons to Hydrocity Zone from Sonic 3. This zone is known for the controversial minecart gimmick that was in the second act in the PartnerNET build, which involved Sonic controlling a minecart in the entire level. Due to responses from the fanbase, the minecart act became an exclusive level in the iPhone version, and the console version received an entirely new act.
The minecart stage in the iPhone release
On August 18, 2010, Lost Labyrinth Zone was revealed on the Japanese website and later on the US site, with a slew of new screen shots. The entirety of Act 2 was altered to use a new torch gimmick, which wasn't in the leaked beta. One screen shot showed the infamous minecart, which was now used differently. Rather than being used in the entire act, the minecart was now automatic, and placed in a few sections during the act. The removal of motion controls from the act was confirmed.
||Eggman began his latest research in the remains of this labyrinth. Mysterious traps including giant boulders, moving walls, and endless waterways deter any curious explorers. If Sonic gets in over his head, make sure to look for air bubbles nearby!
— Description on the Sonic 4 site
Super Sonic will light up the entirety of the console version of Act 2 with his golden glow, making the level much easier. He can also breathe underwater indefinitely.
- Act 1 - Ancient Maze of Mystery
- Act 2 - World of Darkness (Console) / Strange Mine Cart (iPhone & Console Beta)
- Act 3 - Underwater Maze Escape
- Boss - Trap-Filled Ruins
- Jaws - Piranha bots that troll around underwater.
- Bubbles - A blue floating bubble bot. Red spiked variations also appear.
- Orbinaut - Simple sphere bots that move back and forth very slowly. The catch is that they're circled by four spiked balls, which move in a pattern and can only be attacked for a short time.
- Burrobot - Mole bots that leap from the ground and then simply move back and forth in a small area.
- Unidus - These guys look exactly like Orbinaut. They're a bit more hot-headed, though, and will fire off their shield of mines.