Crash Bandicoot: The Wrath of Cortex is a platform game in which the player controls Crash and Coco Bandicoot, who must gather 25 Crystals and defeat the main antagonists of the story: Doctor Neo Cortex, his new superweapon Crunch and Crunch's power sources, the renegade Elementals. Much of the game takes place in a "Virtual Reality (VR) Hub System" created by Coco to help Crash gather the Crystals. The VR Hub System is split up into five "VR Hubs"; initially, only the first VR Hub is available. Each VR Hub has five teleportation portals to different levels. The goal in each level is to find and obtain the Crystal hidden in the area. In some levels, the Crystal will be located at the end of a level or must be earned by completing a specific challenge. Each level contains a "Bonus Platform" that leads to a special bonus area, where the player must navigate through a maze and collect everything in sight. Once a bonus area is completed, it cannot be played again unless the level is replayed.
Source: Wikipedia, "Crash Bandicoot: The Wrath of Cortex," available under the CC-BY-SA License.