The newly-turned Dark Kogaxion rampaged across the planet of Arb, destroying those crystalline life forms. After turning the planet to a wasteland, he flew into space to destroy other species, like the Fantonians.
Ultraman Zero went to Noa's palace in the Land of Light. Seven immediately came to greet him and said, "Wow. I never expected you would actually listen to me." Zero immediately knocked on Noa's door, and the door opened.
"Greetings, high Ultraman Noa. King told me to come here to find out about Ultraman Kogaxion, your adoptive son", said Zero.
"Yes, he was last seen guarding Arb, but a few days ago a few fantonians came to the Land of Light and told us that Ultraman Kogaxion has turned into Dark Kogaxion and is destroying many planets in that galaxy. Please find what is really going on, as I cannot because I have many meetings to attend", said Noa.
"Yes, I will go. Please tell my father that I will set off immediately".
"Yes, I will".
With that, Ultraman Zero flew to Arb, hoping that all the fantonians said were false. However, his hopes were smushed by the fact that instead of green grass all around, there were molten rocks and other signs of destruction. He then flew to the fantonian planet system. When he arrived, he saw similar scenes of destruction. He spoke with a surviving fantonian.
"What happened to Ultraman Kogaxion?", Zero asked.
"Ko-kogaxion came to our planet with a darker state than before his transformation. He shot many Lightning Zagis at our planet, which even before his transformation, he could not do, as that was Dark Zagi's signature weapon", the fantonian said.
"Where did he go?"
"He went to the site of the great universal war."
"The great universal war, where we killed so many monsters, dark ultras and Dark Zagi himself? Why would he go there?", Zero thought. However, trusting what the fantonian said, he set a twinkle way and dove in, arriving near that site of the great universal war. It was there that he found Dark Kogaxion. But in an even darker state than before.