The Brain and Ultra-Humanite took over control of Solovar's group, and enslaved all its gorillas with inhibitor collars. Like the other adults, Grodd was experimented upon with Kobra-Venom, which greatly improved his strength. He was also given brain enhancements that increased his intelligence. It also gave him telepathic abilities, a side effect unforeseen by their tormentors. Solovar and Grodd became peons of Brain and Ultra-Humanite, who made sure they did not rebel by capturing their children.
Grodd was summoned by Ultra-Humanite along with Solovar and several other Kobra-Venom enchanced gorillas to ambush the Team and Wolf. Grodd and Solovar seized them and gave them inhibitor collars, though Miss Martian avoided capture as a result of Grodd telepathically knocking her unconscious while she was in camouflage-mode. Grodd then communicated telepathically with Wolf, who ran away into the jungle to help the Team later.
Grodd and Solovar brought the captives to Brain. Brain still wanted Wolf and Miss Martian captured and sent the gorillas back out with infrared goggles to find them. Grodd, Solovar, Primat and Boka took this opportunity to confront Miss Martian; Grodd demanded her help.
After Solovar told M'gann the story of how their troop came by their telepathic powers, Grodd was astonished and indignant to discover that the powerful telepath now before them was not the team leader. Despite this, M'gann agreed to help the troop get their children back and re-take their freedom.
When Superboy was freed, he punched Grodd, not aware the ape was an ally. It sparked anger in Grodd, but both were calmed when Miss Martian explained the plan.
With Gorilla City destroyed and the humans who had enslaved their troop gone, Grodd and Primat were happily reunited with their child Simeon. While Solovar wondered what their troop would do now that they were free and without the guidance of Congorilla, Grodd mused to himself that perhaps now there was a new future in store in which he could have a larger role.
After the captured heroes escaped, they contemplated liberating the villains, but decided not to and find their captor first.
Kylstar's Vessel December 1, 23:58UTC
The Justice League, Superboy, Miss Martian's valiant effort against Kylstar convinced him to treat his sentient weapons better. All captives, including Grodd, were released, and Orb-One explained Kylstar's motives. He was a freedom fighter who was on a mission to stop slavers who destroyed his homeworld. As a sign of his good intentions, he offered to return captives unwilling to help with his fight back to their homeworlds. Those willing to stay were promised good treatment and glorious battle.
The Collector's Ship December 1, 19:01EST
Grodd, along with all of Kylstar's captives from Earth, were teleported into the Collector's Ship. With the additional reinforcements, the Collector's body was quickly destroyed.
Metropolis December 1, 19:03EST
The body was merely one of many, and the Collector unleashed several additional Coludroids on the assembly. The battle was interrupted when the Collector noticed that the probe he embedded underneath Metropolis was malfunctioning. If nothing was done, Earth would be destroyed. Since the Collector was a preserver and not a destroyer, he agreed to shut off the beam that was slowly shrinking the City. After the assembled heroes convince him of their determination to prevent him from taking the city, he begrudgingly agreed to resize it back to normal and leave.
Metropolis December 1, 22:03EST
The Collector teleported all Earthlings into the city. The villains were nowhere in sight, and the assembled heroes thought that the Collector had teleported them elsewhere to spite them. Unbeknownst to them, the villains were actually just yards away, mentally shielded by Grodd. He told them that they now owe him.