ReBoot - Daemon Rising

An army of infected Guardians invades Mainframe, threatening the system. Hexadecimal, now loyal to Bob, helps him purge the intruders without deleting them. Her energy drain is so great that she is reformatted into a Sprite and encased in a null cocoon that the Matrix siblings recognize as their father, Welman.

In flashbacks, Welman activates his Gateway command just before Bob arrives, bringing the Super Virus Gigabyte to Mainframe's Twin City. The resulting explosion wipes out Twin City and the people there, including Welman, and Gigabyte splits into Megabyte and Hexadecimal. This revelation connects Hex to her current form and sets up the present conflict.

Dot convinces Hex to give Welman a new body made from Nulls, and together they rebuild Welman's Gateway command. The revival sets the stage for Welman to return and influence events on Mainframe. This also restores a pathway for future portal battles.

The Guardians' key tools, which once allowed them to open portals to sealed-off systems, leave the Guardians when Daemon infects them. This robs the Guardians of their primary means to reach other systems, complicating the defense of Mainframe. Bob remains the only Guardian able to create portals because he merged with his key tool.

Mouse, Dot, and Phong manage to seal off a few systems on the Net, creating temporary barriers. When Daemon activates her dormant infection, those unsealed systems resist at first, but the infection spreads quickly across the Net. The result is widespread new infected zones.

During the ensuing battles, Mike the TV, AndrAIa, Matrix, and Mouse become infected and pledge loyalty to Daemon. Their loyalties help Daemon's influence grow across the Net and complicate the defenders' efforts. The Net begins to tilt in Daemon's favor.

Daemon orchestrates Mouse to breach Mainframe, exploiting the infected program to bypass defenses. She needs Bob to help infect the other sealed-off systems. By leveraging Mouse, Daemon edges closer to her broader plan.

Daemon invades Mainframe and infects Bob, forcing him to open portals to the sealed-off systems, a process that drains his life energy. The move accelerates the spread and puts Bob at grave risk as the infection tightens its grip.

Hexadecimal, by absorbing energy from Mainframe's core, regains her virus form and engages Daemon in battle. Despite her renewed power, Daemon—being a Cron virus—overwhelms the defenses and presses toward her final stage.

Daemon decompiles herself to initiate the final stage of infection, triggering a Net-wide binary countdown. If the timer reaches zero, all infected programs will be deleted and the Net will be erased. The stakes are existential for the entire Net.

Hexadecimal sacrifices herself to cure the Net, taking a cure from Matrix's icon after infecting Little Enzo's icon and distributing it to the Net via the Gateway command. Her act restores order and halts the infection, at the cost of her own life.

Bob and Dot become engaged, celebrating their bond as the Net stabilizes. Moments later, a portal opens and Ray Tracer and a pre-Season 3 Bob step through, leaving everyone stunned and unsure what comes next. The ending hints at a larger continuity and new future conflicts.