Batman Unlimited: Monster Mayhem

The Joker needed the powerful battery from the atomic power plant to power his city-wide scheme. He loaded it into an ice cream truck and used it to run equipment that would help execute his technological takeover of Gotham. The battery served as the energy source for the Joker's plan to disable modern technology and seize control of the city.

After stealing Professor Ivo's artificial intelligence and combining it with the battery, the Joker deployed a citywide virus that seized control of every electronic system in Gotham. This included traffic lights, security cameras, and most importantly, Cyborg, whose systems were compromised and forced to help execute the Joker's plan. The Joker used this total technological control to proclaim himself mayor and hold the city hostage.

The Rose Stone is an energy-conducting artifact showcased during the Inca exhibit at Gotham Museum. It was embedded in Cyborg's left arm and served as his power source. When the Joker took control of Cyborg's systems, the Rose Stone became the key to stopping the Joker's mech suit. Following Shoto's instructions, Cyborg placed the Stone on the Joker's mech, causing a short circuit that disabled the villain and restored order.

Clayface kidnapped video game designer Gogo Shoto because his technical skills were needed for the Joker's plan. The Joker forced Shoto to help with his technological scheme, including loading the stolen battery into the ice cream truck. Later, Shoto proved valuable again when he gave Batman a device that could access Professor Ivo's virtual world, which became crucial to defeating the Joker.

Batman used Shoto's device to enter Professor Ivo's AI virtual world and confront the Joker's digital forces. Meanwhile, Cyborg fought to regain control of his own systems with Shoto's guidance. The turning point came when Cyborg placed the Rose Stone on the back of the Joker's mech suit, triggering a dramatic short circuit that sent the Joker plummeting into the sea and caused all electronic systems to reboot, ending the crisis.

After seizing control of Gotham's electronics and creating chaos throughout the city, the Joker took political control by proclaiming himself mayor and installing a cabinet of his villain allies. This was part of his broader plan to normalize the mayhem and cement his control over Gotham. Batman discovered the Joker was planning a grand parade to publicly solidify this new regime.

Clayface has shapeshifting abilities and transformed into a Tyrannosaurus rex to cause maximum chaos during the museum exhibit. This wasn't just random violence, it was part of the villains' coordinated attack to disrupt the event where Cyborg's Rose Stone was being showcased. The dinosaur rampage forced the heroes to split their attention and created an opportunity for the Joker to advance his technological takeover.

The Joker used his citywide virus to hack into Cyborg's cybernetic systems, pulling the hero into his dark plan and forcing him to help execute the technological takeover. Cyborg was coerced into facilitating the scheme against his will. He only regained control after following Shoto's guidance to reconnect with his systems and discover the Rose Stone embedded in his arm.

Professor Ivo created an artificial intelligence that the villains stole from him. Combined with the stolen battery, this AI became the core of the Joker's plan to take control of Gotham's technology. The AI existed in a virtual world that Batman had to enter using Shoto's device to confront the Joker's digital forces. Without this AI, the Joker's citywide electronic takeover wouldn't have been possible.

The heroes tracked the villain gang to an abandoned amusement park on the Gotham pier for the climactic confrontation. During the battle, they freed Gogo Shoto from captivity and brought him back to the Batcave. This location served as the final showdown ground where the heroes ultimately rescued Shoto and gathered the information needed to access Ivo's virtual world and stop the Joker.