CrossWorlds

CrossWorlds is an MMOG (Massively Multiplayer Online Game) developed by Instatainment that blends virtual reality with an actual physical environment. The majority of CrossCode takes place within CrossWorlds, focusing on Lea's playthrough of CrossWorlds.

CrossWorlds takes place on a small moon which has been purchased by Instatainment and completely designated for the game. Remote players are linked to artificial bodies, or Avatars, and can physically interact with the landscape of the moon. As such, CrossWorlds employs a unique mixture of physical construction and virtual, programmed elements in its design. The majority of game constructs, including the Avatars, are made of Instant Matter, a remotely controllable material used throughout the moon.

Gameplay
Although CrossWorlds does not charge high fees to play, the technology required to connect to an Avatar, known as the Cross Gear, is prohibitively expensive. As Lea went through a non-standard entrance to the game, the exact details of registering are not known, but class selection and Avatar customization are involved. New players go through the Rhombus Dungeon tutorial area to learn gameplay basics, but experienced players starting a new Avatar are given the option to skip this.

The main gameplay of CrossWorlds is based around puzzle-solving and combat. Dungeons are largely puzzle-based, with a wide range of Puzzle Elements to challenge the player. Enemies made of instant matter are commonly found throughout the game world, and can be fought for gold, experience and items. Virtual treasure chests are scattered throughout the world, and are instanced for each player. Items and equipment are virtual gaming abstractions, explaining why they don't affect the appearance of avatars and why an unlimited inventory is possible. Sidequests and item trading are frequent features offered by NPCs or other players, particularly in city areas.

Plot
In CrossWorlds, players (referred to in-game as Seekers) are enlisted in Operation Trackwalker and tasked with following the Track of the Ancients, a series of challenges left behind by the mysterious Ancients. This involves traveling throughout the many areas of the moon Shadoon, overcoming the Track's various creatures, and exploring abandoned temples to rediscover lost technology. Over the course of the game, Seekers obtain power of the four elements of Heat, Cold, Shock, and Wave to further assist them in combat and puzzles. Once enough Seekers have traveled the Track, humans hope to use it to their advantage instead of destroying it.

Characters
The game makes use of NPCs, which are Avatars controlled by a somewhat simplistic artificial intelligence, for players to learn from and interact with. There are also many human CrossWorlds employees, who live and work on the moon and may interact with players.

Technology
Many complicated programs are involved in controlling the Instant Matter and virtual elements of the game; the exact method by which this code is implemented is unknown and probably unimportant to the story. The control code for Avatars in particular is stated to be exceptionally complicated, explaining why Sergey has such difficulty fixing Lea's speech problems.

A few physical devices allowing maintenance staff to interact with the game have been shown:
 * AR Goggles make the game's virtual elements visible to humans, as these don't really exist; they're normally only visible to Avatars
 * Jet uses a device that allows him to throw Balls when he teaches Lea combat
 * Carla is able to use a tablet interface to create Instant Matter steps
 * Jet uses a Neutralizer to get rid of the Blue Avatar, which is shown to deconstruct all nearby Instant Matter

Credits
The currency used in CrossWorlds is called the Credit.

Credits are obtained by killing enemies and completing quests. Credits are mainly used to buy items in shops and required for trading. In old versions it was also possible to reset the Circuit tree by spending Credits.