Gamera, Zilla, and Titanosaurus gawk at the enormous, crocodile-like Anteverser. The only solace Gamera can find is that it is obviously not Bagan. The submarines inform them that they will have to do their best to knock it back into the Rift so that they can destroy it. The three split up and it starts chasing Zilla, easily breaking through the rocks he tries to hide behind. The three counterattack and start ripping out the creature's scales, trying to create a weak spot. When it tries to devour Gamera, he fires a flame stream down its throat, making it draw back.
Before they can press their attack, the Anteverser starts speaking to them, shocking them as no Anteverser displayed sentience before. It egotistically calls itself Creation, the greatest achievement of the Anteverse's masters, and Earth's victories against them end here. Creation attacks and slams Titanosaurus down. Enraged, Zilla blasts it in a wound with a napalm blast, making it chase him. Gamera quickly heals Titanosaurus' ribs and arm with magic, and she questions Zilla having a beam attack, as she's never seen him use one before. He explains that it drains his reserves quickly, so he can usually only use it once per battle.
As the submarines observe the battle, their sonar detect two large unknowns approaching their position, one from under the ocean floor. Then they detect more Anteversers coming from the rift and warn their Kaiju allies. They launch their torpedoes at the new enemies, but the enraged Creation unleashes an electrical blast that destroys the torpedoes from miles away. The crews groan that it seems hopeless, but Carrie White has made telepathic contact with the two unknowns and says they are friendly.
One of them arrives and makes mincemeat out of the new Anteversers. Zilla and Titanosaurus gawk at her and ask who she is, but she tells them to fight now and ask questions later. The newcomer attacks Creation's tail, distracting it long enough for Gamera to blast it several times. Weakened, it starts to sink. Gamera stares at the newcomer, who resembles a hybrid of Zilla and Titanosaurus, and asks who she is. She introduces herself as Tytanna, and explains that she was observing them from a distance and decided to help. Gamera extends his senses and is shocked. Out of all creatures he had encountered, only Mothra and his fellow Guardian Beasts possess magic in their bodies, yet Tytanna does too.
Creation roars that it has had enough and now they will face its true potential. Another swarm of Anteversers emerge from the rift. Tytanna grins and says they have backup of their own. The volcano erupts and Obsidius emerges, now back to full strength.
Shocked, Titanosaurus asks what he is doing here and Tytanna says she convinced him to help. The group of five attacks the Anteversers. Titanosaurus is worried about Obsidius, but he assures her that he wants to help them, because they are his friends. She tells him Creation is the biggest threat, so he warns her to move everyone away. Meanwhile, the submarine crews hate sitting there doing nothing, but agree they must wait for the right opportunity.
Obsidius wipes out Creation's supporters and injures it with lava blasts. The others stare in amazement. Obsidius is now so powerful that his blasts may be able to injure Godzilla Junior and Anguirus, who are normally immune to lava. Creation declares that it is through holding back, and its injuries heal. Zilla protests that none of the Anteversers displayed a Healing Factor before, and Gamera can sense that it is using magic to do so. Creation gloats that its victory is inevitable. While Obsidius draws power from the volcano, it draws power from the Rift, an inexhaustible energy source.
Obsidius declares that it doesn't matter. He will not fail his friends. Creation mocks him and says concepts like friendship are meaningless. All of the Kaiju present declare that is bullshit. The bonds between them are what make them superior to the Anteversers. No matter how advanced they claim to be, they will never conquer Terra, for they are facing multiple races working together. Gamera gathers the mana between them and pools it into Obsidius, supercharging him even further. Creation roars at them to die and fires a beam over fifty feet wide. Obsidius counters with his own beam and they have a Beam-O-War. The power unleashed shatters the barrier protecting the Rift. As the two struggle, one of the submarines sees an opening and fires a nuke at Creation.
Obsidius shields the others with his body, but the shock wave still throws everyone for a loop. Tytanna's body shrinks a little, causing her to complain and say her mother is going to be pissed. Before they can ask her what she means, Titanosaurus frantically checks on Obsidius. He's incredibly weakened, but all right. Before they can celebrate, Creation reveals it is still alive, though horribly injured. It tries to finish them off, but Obsidius latches onto its head, severely burning it. Obsidius orders everyone to retreat, and solemnly knows this last act will kill him. They solemnly swim away, dragging Titanosaurus with them kicking and screaming. She begs him not to do this, but he says this is the only option that results in the least amount of casualties. He thanks her for their time together. Xenilla created him as a tool for war, but she showed him that life is more that that. With the last of his power, he triggers another volcanic eruption that completely engulfs the Rift and Creation in lava. Obsidius' body falls apart and his essence merges with the volcano. Taking it further, he uses the lava to force Creation back into the Rift, causing it to open and allowing Obsidius to send the full force of the volcano's lava surging through it for over a minute until the Rift finally collapses and Obsidius dies.
Everyone stares at the scene and mourns. The submarine captains shakily declare the mission complete.