A former military comrade of Duane's gets hired at Quark. He quit the military because he thought the pursuit of a robot without a human was wrong. Now he has created his own version of Big Guy, ""Hard Drive"", and with it plans to destroy what he thinks is a pure robot.

Big Guy and Rusty go back in time to the civil war.

Donovan's nephew, Pierre, is working on a robot for the school science fair. He uses the brain of the Legion Ex Machina's #4, who was recently captured by Quark. When it's activated, trouble ensues.

Quark develops a protoplasmic, semi-intelligent blob that doubles as a cleaning agent. The title is given as a ""Squeaky Gleem"".

When Quark's Dr. Kirby disappears after an experiment with his Quantum Machine goes awry, a hostile monster emerges and goes on a rampage, apparently having destroyed the doctor. Back at Quark, Rusty discovers a previous ""boy robot"" prototype. Hoping for a new friend, Rusty reassembles the robot, who he names ""Earl."" But Earl's relentlessly aggressive programming turns him against the heroes.

A family of aliens, made of organic metal, come to earth seeking refuge from their pursuers, evil insect-like robots.

Being powered up for six months, Rusty has not grown an inch. Frustrated that he will never be as big as The Big Guy, he connects his robot head on the powerful robot body of Quark's T-7000 Prototype. But he learns there's more to crime-fighting than just being big when a gang of exosuit-wearing chopshoppers (Gage, Big Rig, and Cargo) lure him into an ambush.

Big Guy and Rusty journey to the heart of a volcano that erupted in the city to deliver a Cobalt Thorium-G Bomb. They are suddenly attacked by magma creatures, who turn out to be the ones engineering the volcano in an attempt to take over the surface world.

On Quark Industries' recently christened space station, the computer, known as Edie, has gone mad. Threatening to destroy the moon, Edie demands delivery of the Ubik Chip, which would allow Edie to gain control of all computers on Earth.

Donovan unveils Quark's latest prototype: tiny liquid metal robots called Nurds that repair and upgrade any technology they come in contact with. When Big Guy becomes infested by the Nurds, they repair its original artificial intelligence circuitry, making Big Guy a fully functioning robot, which removes Dwayne from the pilot's seat. But shortly after the new Big Guy successfully completes his first mission, things go awry.

While trying to keep the Legion Ex Machina's newest robot from absconding with Quarks' new anti-neutrinos, Rusty plugs into the bot's software to learn the Legion's secrets. #4 counters Rusty's hack by engaging in a mental tug of war. A power surge switches personality traits between the two robots. Rusty starts building a doomsday machine while #4 plays video games.

The Legion Ex Machina downloads Rusty's programming in an effort to learn his secrets. Rusty, Big Guy and the Evil #4 end up in a showdown in cyberspace.