|Fourth/Ninth level, Sonic Adventure|
|Number of Acts: 3|
|Level theme: ancient ruins|
|Underwater areas: Yes|
Lost World is the ancient ruin level of Sonic Adventure, accessible only by Sonic and Knuckles. It is well known for having screenshots of Knuckles in areas he can't access in the final version, as well as being chased by giant rocks, Indiana Jones-style.
It is here that Perfect Chaos is revealed to Sonic for the first time, though he does not recognize what it is at the time.
The level is accessed inside the South Temple, in the jungle ruins of Angel Island, and runs throughout the subterranean waterways beneath the Mystic Ruins. Being located under the ruins of the Echidna civilization, which itself bears resemblance to Marble Garden Zone from Sonic 3 in its past incarnation, this stage likely correlates with the area represented by Hydrocity Zone (similar to Sonic Adventure's own version of IceCap Zone).
This is the first part of the level that is only accessible to Sonic. It has mini streams all over and a long hallway with flame throwing rocks. Once getting past this Sonic will enter a large room with a wooden snake in the water. To get past this area, Sonic must activate the 4 water level switches and the three door switches to open the door at the top of the level. To access the switches Sonic must hit the water level switches, which raise the water level, then ride on the wooden snake to the switches. Being careful is reccomended because there is a bottomless pit under the whole level. Once past this area Sonic will go into a dark cave. In order to complete this area Sonic must move the light panels onto the mirrors. Once making it past there, Sonic will go to an area with a large waterfall that will lead to the next area...
This area consists of two main setpieces. The first is a dark room with few light sources and a set of mirrors. Sonic must approach the mirrors and angle them between these light sources and other mirrors in order to make the path through the section visible. In SADX the difference in lighting is significantly less severe, making it possible to finish this section without lighting the pathways. This leads Sonic to a waterfall, which washes him away to the next section.
The second major setpiece is, as the name suggests, a chase across a long stretch of road where Sonic is chased by a large boulder, much like in the Indiana Jones films. The camera is placed in front of Sonic, and he must run toward it, like in the start of the snowboarding segment of Ice Cap. This makes it harder to grab rings and items, but as there are no obstacles, it can be completed by running straight ahead toward the end.
After this is done, a doorway opens leading directly into the next segment (that is, there is no pause in between these two segments as Sonic).
Sonic and Knuckles both access this area. This area is a maze of anti-gravity puzzle floors. The player must push the buttons on the floor to make the floor pieces on the wall. Once the tiles are lighted, it is possible to walk on them. Sonic must do this in order to beat level.. Once reaching the top of the level, the player must hit a switch to activate light rings. Light Dash on them to make it to the other side of the room. Once there, the will go through a few loops and reach the end with the Picture of Chaos.
Knuckles has only the main room access. He can still do the floor puzzle, but it is unnecessary. He can go everywhere in this level Sonic can, except for the room with the mural.
|Sonic the Hedgehog|
|Level number: 9|
|Maximum rings: 489 + (7-280)|
|A-rank requirement: 4m 30s|
|Knuckles the Echidna|
|Level number: 4|
|Maximum rings: 103 + (5-200)|
|A-rank requirement: 1m 0s|