What is "Warcross" in the novel, Warcross?

Warcross is a virtual reality video game that can be accessed through the use of NeuroLink glasses or contact lenses made by Henka Games. It is the most popular game in the world and can often have real world consequences in terms of money and status. Each level of Warcross takes place in a different arena, such as a snowy landscape. Later in the novel, the author reveals that Hideo based the uber-successful Warcross off of a simple childhood game that he used to play with his little brother Sasuke before he disappeared.