This episode is where a mysterious robot called the Robotrix appears and attacks Lyon.
It starts where Lyon is swinging on his swing very high. When he almost swings around the bar, he turns into Jetray and flies towards the roof of his house. He then turns into Spidermonkey and leaps onto the roof. Lyon then yells out, "Awesome!" He then realizes it's time for dinner. He turns into Humongousaur, and then Opposite Humongousaur to go down the chimney. He turns back into Humongousaur and then Big Chill, who freezes the fire. He then smashes the ice, then quickly flies into his seat and turns back into Lyon just as his siblings, mom and dad get in their seat. He quickly eats his dinner, being the first one done. He puts his plate on the counter and runs up onto his alien computer, a device that tells where trouble is.
He sees a red mark coming towards him, which is a green mark on the computer. He then quickly turns around and sees a figure with gray skin and red and green clothes. Because of the gray skin, Lyon suddenly notices it is a robot and turns into Goop, which constricts the robot. The robot turns green, and then turns into a small, yellow dragon while yelling out, "Electridragon!" the robot turns into a beam of light and travels into an outlet. Lyon also slips into the outlet, but since the U.F.O. can't fit, the goo falls down. The robot slips out as a bigger beam of light, and then turns into a orange, regular-sized dragon. Lyon gets shocked and slips out of the outlet and back into shape. Then Lyon throws goo at the robot while the robot shoots lightning at Lyon. His mom comes upstairs. Lyon turns back into normal and hides the robot under his bed.
Lyon's mom says that the family is going to the aquarium. Once they do, Lyon sees the robot. He has green skin. Lyon runs toward the robot, but Lyon's mom stops him and says, "We have to admire the fish and stuff." Lyon says he has to go to the bathroom, and then runs in. He sees that the toilet bowls are fish bowls and the urinals are sideways fish tanks. He then says, "That's just nasty" and turns into Opposite Humongosaur. He looks around. He sees a giant clam with a pearl in his mouth. He says the clam should go back into his tank, but he sees a gray hourglass symbol. "The Robotrix!" yells Lyon as he gets under the clam. He then turns back into regular Humongousaur and knocks the Robotrix, an alien called N-NME, into the water. Everyone sees something in the corner of their eye. They turn and look, but Lyon is Brainstorm in a tank, because Brainstorm was the most fish-like alien.
Brainstorm/Lyon attacks N-NME/Robotrix repeatedly. N-NME launches the pearl up into the air with his tongue, then spikes it down. It explodes in Lyon's face. Lyon turns into Opposite Brainstorm and launches the Robotrix into the ground. The Robotrix's pearl then goes down in his throat, and then Robotrix doesn't do anything. After a few minutes, Robotrix's skin turns green. Robotrix is a long fish with an orange face and tail. The fish is wearing a top hat. A purple spring separates the head from the other part, which has two fins and a tail. Robotrix yells out, "Coifish!"
Robotrix spins around and does a whirlpool attack. Lyon is knocked against the wall. Robotrix then coils up, turns around, and coils out, which whips Lyon in the face. Robotrix does many other attacks, like a ground pound, whip, tornado spin, etc. Robotrix then turns into a hazy alien called Hazehail, absorbs Lyon's energy, and disappears.
Lyon turns back into Brainstorm, leaps out of his tank towards his family, and turns back. His dad asks, "What took you so long?" Lyon says, "I guess time flies."
Lyon's family goes back home after an hour. Lyon uses his computer to track down Robotrix, which is at the city. Robotrix is an alien called Mothfly. Lyon opens his window, turns into Big Chill, and flies to the city, where Mothfly is breathing fire. Lyon turns into Opposite Big Chill and traps Mothfly in a fire blob. Robotrix does a spin attack which fans the fire blob away. Lyon attacks Robotrix a lot. Robotrix freezes Lyon. Lyon is trapped for a while, but then he does a fire blob on himself to melt the ice away. Lyon flies very close to Robotrix. Marked on the top of the Trix, Lyon sees the letters, "H I G H B R E E D" on it. He then turns back into Lyon and tackles Robotrix down to the ground. Lyon sticks the Oppositrix onto Robotrix's Trix. It is a perfect fit. Robotrix turns back to regular, and then falls apart. Everyone cheers.
Lyon walks proudly home. As he walks in the door, his mom nags and says, "Lyon Midd Niner! You have been out of this house for a while! Me and your father have been looking for you! Is that a piece of metal in your ear? Are your shoes sticking to your back using static electricity? Is that a burn mark on you?" Lyon says, "Mooo-omm!!!!" Then it shows Robotrix's parts coming back in place, and then his eye opens.