Lost World


 * Not to be confused with the video-game Sonic Lost World.

Lost World (ロストワールド) is one of the action stages featured in Sonic Adventure. It is located in an ancient Echidna temple in the heart of the Mystic Ruins jungle area.

Description
The stage can only be accessed in one of two ways: through the main entrance during an earthquake (Sonic), or through a vent at the back of the temple which can be unlocked by 2 stone keys (Knuckles).

The level is divided into three main parts: a long maze-like section that ends with a flooded room where switches must be pushed to open the door, a dark passage with a waterfall and bolder running segment, and a room with panels that can be walked on when aligned. Sonic goes through all three, while Knuckles goes through only the third. Skill and timing is required to master this level.

Gameplay
There are five sections scattered across the stage. The first one has a large swimming snake, which must be used to find three switches to open a door,of snakes. The second room is dark, and mirrors can be used to light it up. The third area has a waterfall, which leads to a pond with stepping stones resting in the water, followed by having to escape from a giant burning boulder headed straight for the player (reminiscent of the opening scene of Indiana Jones and the Raiders of the Lost Ark). The fourth is a giant room, which must be slowly climbed up using mystical platforms that allow the character to walk on walls. To walk on the panels, the player must connect a group of them with a nearby switch, and once they are lit, the character can walk on them. Knuckles plays only in this area, and his ability to climb and glide makes it much easier. The final short area has two small ponds with a stone mural of Perfect Chaos, destroying the ancient Knuckles clan. This also foreshadows what will happen in Super Sonic's story.

Trivia

 * There is a glitch in Knuckles' stage that will allow him to access Sonic's entire portion of the level. Ironically, the same music is playing as in Sonic's music is completely different. The same glitch also allows Knuckles to complete the stage where Sonic would. What the player has to do is punch one of the blocks before the fire comes out and Knuckles will glitch through.
 * This is the only stage in Sonic Adventure that only two characters can access, as opposed to three in all other stages. Additionally, this is the only stage in the game that is exclusive to Sonic and Knuckles.
 * Time can be saved in Sonic's A-rank mission by running backwards on the giant snake instead of waiting for it to complete its loop around the room. Also, if one were to memorize where the platforms are in the dark room, then the entire section with the mirrors can be skipped to save time. Interestingly, the DX version of the game brightens up this area, rendering the mirrors completely unneccesary.
 * In Knuckles' version of this level, different music is played that isn't heard when Sonic goes through the same area. Sonic can hear this music for about a split second in his stage's last room (then the stage ends).
 * The stone mural of Perfect Chaos shows what the designers intended him to look like. It was not shown in Sonic Adventure because of the technological limits of the Dreamcast, but his true form was shown in Sonic Generations during his boss fight.
 * In addition, the mural was stretched and mirrored in the final game.