Leo and a team of scientists are studying the various remains of Zonder robos. Leo notes that the Zonder crystal’s structure is almost like a living being instead of a machine. He wonders why they need human hosts, and the computer analysis shows that if a Zonder reaches maturity it could disperse Z0 particles across the whole world. Later, Leo and Swan visit Isolde, a large particle accelerator in Hokkaido. They are greeted by Isolde’s designer Tohru Nozaki while Volfogg watches them discretely from the forest. Nozaki boasts that Isolde is the largest particle accelerator in the world, but Leo tells him that the experiment is more important than the machine’s power. Nozaki leads them to the main beam emitter room to provide a demonstration. In a nearby village, Hana is visiting her grandmother, who tells scary tales of terrible things that will happen when the gates of Isolde open. As the particles collide, Nozaki marvels at the large energy reaction but Leo wonders if the amount of energy won’t hinder the acceleration. Nozaki assures him that the particle beam can melt through any metal instantly, including that of the 3G robots. Leo and Swan spot a strange reaction in his eyes and instantly get suspicious. Nozaki leaves them to tour the place on their own. He heads into an underground cavern and rides a platform towards a Zonder metal plant. As he reveals himself to be a Zonder, Pasdar contacts him. Nozaki tells him that thanks to the Zonder metal Isolde can output an immense amount of power that he can use to grow as much Zonder metal as he needs. Pasdar is concerned that GaoGaiGar might show up, but Nozaki is counting on it. Leo and Swan enter the cavern and are shocked at what they see. Volfogg sends an emergency signal to Entouji and the Triple-decked Flying Carrier is launched immediately. Onboard, Mamoru reveals that he used to live on Hokkaido up until he was five. Guy is silently hoping that Swan and his father are alright. Mamoru can sense the Zonder, but feels that something is different about it. Guy, HyoRyu and EnRyu infiltrate Isolde separately through three of its four gates, and Hyuuma tells them that because of the electromagnetic fields they won’t be able to maintain contact. Mamoru spots a blip on the screen heading towards the fourth gate, which turns out to be Volfogg.
Inside Isolde, EnRyu encounters Primada while HyoRyu runs into Polonaise, whose structure he can’t analyze. Polonaise announces that he’s an advanced man-machine hybrid that can’t be comprehended by a mere Earth robot. Guy runs into Pizza, who introduces himself as one of the four Machine Kings. Declaring that Isolde belongs to them, Pizza attacks Guy and overwhelms him with his speed. However, Guy activates his Hyper Mode and gains the upper hand. The wounded Pizza escapes and Guy is unable to follow because his Hyper Mode reached its limit, so he summons Galeon. Elsewhere, Penchinon encounters Volfogg and is struck by his large Silver Cross shuriken. GaiGar, HyoRyu and EnRyu meet up at Isolde’s command center, where Nozaki finally merges with the particle accelerator and becomes EI-12. EI-12 traps the 3G robots with an electromagnetic field while Pizza, Primada and Polonaise gloat over their victory. However, a battered Penchinon appears and warns them that there’s a fourth robot. On cue, Volfogg appears and cuts the trapped Leo and Swan loose. They take the trapped scientists and escape outside. Pizza can’t believe that a robot is able to move freely in the electromagnetic field, and Penchinon tells him that this one is different. Volfogg uses his Silver Moon blades to disable the field and free the other 3G robots. Guy summons the Gao machines and performs Final Fusion. EI-12 wrenches the accelerator’s beam lines loose and knocks Volfogg away with them. It fires a particle beam at Guy, which he reflects with Protect Shade. The shot goes through the cavern’s ceiling and out to the surface, where Hyuuma orders the Dividing Driver to be launched at its point of origin. HyoRyu and EnRyu intercept it with their cranes and Guy uses it to create the repression field. Not wasting any time, Guy quickly locates the core and uses Hell and Heaven to extract it, destroying the Zonder metal plant and forcing the Machine Kings to retreat. As Nozaki is purified, Leo muses that it may have been a mistake to put him in charge of Isolde because all he wanted to do was push the limits of the particle accelerator’s energy source. Volfogg appears and reports that he managed to recover an intact Zonder metal crystal from the remains of the plant.
This episode is so jam packed that I barely know where to start. Let’s get the goofy out of the way: Why did the gates of Isolde have lock mechanisms designed expressly for HyoRyu and EnRyu’s hands? And what was up with the color coded lighting inside the tunnel scenes? That aside, we got several interesting developments here. Pasdar finally started employing Zonderized humans to covertly carry on his agenda of constructing Zonder metal as opposed to public acts of mindless destruction. Presumably Nozaki was able to revert to his human form like the pizza delivery girl from before so he was probably Zonderized for a few days at least, though it’s unknown how much of his free will was retained. The Machine Kings finally introduce themselves to 3G in a setup that implies an emerging rivalry between each pair. Volfogg gets a pivotal role here, but it seems they’re still saving his full debut for later.