Rez (2001)

To resolve the world's rising crime rates, a new system called Project-K was created. However, Eden, the core of Project-K, has fallen into a vegetative state. Now it's up to you, a hacker, to travel through a cyberspace filled with firewalls, viruses, and other obstacles, and jump-start the system's artificial intelligence. Scattered throughout the levels are evolution spheres, which let you transform into more powerful humanoid forms.