Disguised as an upgrade, Megabyte enters Mainframe's core control chamber. He badly hurts Phong and initiates an Erase Command that almost destroys the System, only to be thwarted by Bob exploiting his greed.
A code master from the Net is searching Mainframe for a code master by the name of Tallon. It seems crotchety old Mr.Pearson might have some information to share.
Megabyte's continued attempts to steal Mainframe's energy lands Bob and Enzo in a corrupted Mad Max gamecube. With all of Mainframe's energy at risk for nullification, Bob must keep both the Users and the sprites from winning the game.
With no other young sprites in Mainframe, Enzo is lonely. When an aquatic game drops on the diner, Enzo makes friends with a game sprite named AndrAla.
Something horrible comes through Hexadecimal's looking glass, mutating her into a black supervirus. The nulls launch an offensive on her, creating a gigantic null monster.
The entity that came through the looking glass attacks and corrupts Megabyte, who then merges with Hexadecimal, transforming the two of them into Gigabyte, the next generation of virus.
A portal to the Web hovers over Mainframe, and its citizens must prepare for war. Due to the situation Bob gives Enzo a commission as a cadet guardian. Megabyte and Hexadecimal join the battle, but they have a secret ulterior motive.