Lake Ashino, the current residence of Gaira, the Green Gargantua. After reports of missing hikers and a giant monster, the JSDF decided to investigate. By the time they arrived on the scene, nighttime was quickly approaching. Several tanks and maser cannons assembled near the coastline, waiting for whatever might appear. They didn't have to wait for long...

The Green Gargantua rose out of the lake and let out a gluttonous shriek. The humanoid was met with an onslaught of tank shells and maser discharges. Gaira shrieked as several shells hit his chest and three masers blasted him in the stomach. Though the masers wounded him, the attacks angered him more than anything.

In a blind rage, Gaira rushed towards the JSDF vehicles and mercilessly attacked them. The humanoid grabbed a maser cannon and threw it at a tank that was firing at him, causing both to explode. The JSDF forces started to pull back, but the Gargantua wasn't going to let them leave so easy. Gaira smashed and threw any vehicle he could get his hands on. The JSDF forces were devastated by the monster's assault. The Gargantua started to sift through the destruction to search for any humans to eat. After discovering a few, the creature began to gorge and satisfy its sickening appetite. Though Gaira won this match, the true battle was about to start...

Erupting forth from the ground was Anguirus, awakened by the fight between Gaira and the humans. The mutant ankylosaurus saw Gaira holding a tank and chewing on a human. Anguirus angrily roared a challenge to the giant humanoid as he shook dirt and foliage from his carapace. Gaira gulped down the human he was eating, and shrieked in retaliation.

Anguirus charged at Gaira only for the Green Gargantua to smash Anguirus in the face with the tank. The attack was strong enough to send the large dinosaur toppling on its side. Gaira quickly kicked Anguirus in the chest, flipping the quadruped onto its back. Gaira attempted to stomp on Anguirus' head, but the dinosaur rolled out of the way before the attack could connect. Anguirus then lunged at Gaira's left leg and sank his teeth into it. Gaira raised his head and shrieked into the night. The Gargantua started to bash Anguirus in the head repeatedly with the tank until Anguirus finally let go. Blood started oozing from the humanoid's wounds. Anguirus felt a bit dizzy from the blows, but shook it off. Gaira threw his battered tank at the saurian, but Anguirus smacked it away. The armored dinosaur retaliated by rearing up and slashing Gaira in the chest with his claws, causing the green humanoid to stumble backwards. Gaira looked down at his chest wounds, then back up at his foe. Gaira howled at his armored opponent. Revenge was the only thing on his mind now.

Gaira charged recklessly at Anguirus, but the giant dinosaur swung his tail at Gaira, hitting him in the face. The giant fell to the ground accompanied with a sickening thud. The attack had broken Gaira's nose and created a gash on his forehead, causing blood to wash over his face. Gaira got back up and waved his arms at Anguirus furiously. He wasn't going to let his enemy do this to him. The two creatures then charged as Anguirus stood up, and grappled each other. The monstrosities tried to overpower one another, but to no avail. Anguirus leaned in on Gaira and chomped on the Green Gargantua's right ear and tore part of it off. Gaira screamed and kicked the large dinosaur in the gut in retaliation. The blow sent Anguirus flying backwards and landing on his spiked shell. Gaira roared at Anguirus and kicked his fallen foe in the ribs, causing Anguirus to moan in pain. Gaira turned to see that the lake was not too far from him. This gave the Green Gargantua an idea. As Anguirus got up and turned around to face his enemy, he saw that Gaira was heading for the lake. Anguirus gave chase but Gaira made it to the lake before Anguirus could catch him.

The Gargantua managed to dive underwater, the cool waters of Lake Ashino rejuvenating his body. Gaira soon rose out of the lake and was ready to face the spiked saurian who was in pursuit. Anguirus had fallen for the giant's trap as they were fighting in Gaira's domain now. Anguirus lunged at Gaira in an attempt to tear his throat out, only for the green giant to quickly kick the saurian in the jaw. Caught off guard, the hit caused Anguirus to bite his tongue by accident. The dinosaur whimpered in pain, blood oozing out of his mouth. Gaira shrieked with delight while the dinosaur snarled at his enemy. The green giant's gloating didn't last for long as the armored kaiju lunged once more, this time tackling Gaira. The two monsters started thrashing about in the water as their conflict intensified. After a few moments, Gaira managed to get on top of Anguirus. The Gargantua clutched his hands around the saurian's throat and began choking him.

Gaira's grip was firm and showed no signs of letting go. He had managed to keep Anguirus submerged, hoping that the combination of the strangling and the water would end him quickly. Anguirus was feeling woozy. He knew that he needed to free himself from Gaira before the monster could strangle him to death. Anguirus started flailing his forelimbs at the green giant and managed to slash his claws across the Gargantua's face, making a large gash in the green giant's left cheek. Gaira cried in pain and released his grip as he pushed away from the dinosaur, covering his face in response to his immense pain.

Although his grip had only been released for a moment, that was all that was needed as Anguirus' form quickly burst forth from the water. Breathing deeply, the saurian's eyes burned with hatred towards the green monstrosity. Anguirus charged at Gaira and bit down on the giant's leg and pulled it hard enough for the Green Gargantua to lose his balance and fall, creating a large splash. Anguirus shook his head wildly like a mad dog, tearing flesh from Gaira's leg. Anguirus climbed on top of Gaira and put one hand on his face, biting down on his right shoulder. The Gargantua's scream was muffled due to Anguirus covering his mouth with his hand. Gaira searched for something to hit Anguirus with. He found a small boat and smashed it into the saurian's face. Anguirus cried out in pain as part of the boat splintered into his left eye. Anguirus rolled off of Gaira and headed back towards the mainland while the Gargantua was still recovering from the damage suffered to its leg. Once he got out of the lake, the dinosaur furiously tried to remove the piece of wood embedded in his eye.

Gaira rose up and noticed his foe tending to his own wound, too busy trying to remove the splinter in his eye to fight back. The Green Gargantua took advantage of this, rushing out of the water and seizing the armored dinosaur's tail in an attempt to drag him back into the lake. Anguirus quickly felt the tug on his tail, realizing that it must be the emerald giant. He swung his tail hard enough to send Gaira crashing to the ground. Gaira quickly got to his feet and roared at his foe, grabbing a nearby tree and uprooting it, ready to bludgeon Anguirus with it.

The green giant repeatedly smashed the tree on top of Anguirus' head; however, this only infuriated the saurian, who reached out and bit down on Gaira's forearm. As the Gargantua released the tree, Anguirus opened his jaws to let go of Gaira's forearm and instead chomped down on his hand. Gaira screamed in pain and started punching Anguirus in the head. The giant dinosaur ignored the punches and started shaking his head, hoping to tear off a lot of flesh from the emerald monster's hand. Gaira finally forced Anguirus to let go of his hand by kneeing him in the throat. The flesh on his hand was shredded by his foe's attack, pieces dangling off of his hand. Anguirus took a few steps back and gasped for air. Gaira took advantage of this and rammed into Anguirus, knocking the saurian down to the ground with the gargantua on top of him. Gaira leaned in and bit down on Anguirus' throat, tearing it open. Blood gushed out of the dinosaur's neck and soaked the ground. Gaira roared with delight, but the delight didn't last long.

The hairy giant soon felt pain in his back. The Green Gargantua turned around to see that another group of tanks and maser cannons had arrived and began firing at him. The army continued its assault, firing at both Anguirus and Gaira. Gaira climbed off of Anguirus and roared at the vehicles. Several tank shells and masers blasted the green giant's chest. Gaira grunted in pain and grabbed Anguirus' tail. Using all of his might, the Gargantua started to swing his enemy around as hard as he can. Just as he was about to throw Anguirus at the vehicles, a maser hit Gaira in the face, causing him to toss Anguirus into the side of a mountain. The saurian made a loud thud when he hit the mountain, several rocks and trees falling onto him. The armored dinosaur coughed up some blood and laid motionless for a while.

Gaira roared in anger at the military as they kept firing at him, his anger making him oblivious to his spiked adversary. The armored saurian soon regained consciousness just in time to see Gaira heading towards the JSDF forces. Gaira ignored the tank shells and masers, but he couldn't ignore the pain that he felt next. Rushing forward, Anguirus slammed his spiked tail into Gaira's right side, slamming the green behemoth to the ground. A sickening crunch was heard shortly after Gaira fell. Three of his ribs had cracked. Gaira moaned in agony, clutching his side.

Anguirus coughed up more blood. He was starting to lose consciousness due to blood loss. The enormous dinosaur started to walk towards Gaira, even though movement was getting to be difficult for him. The Gargantua was getting worn out from the fight as well and had also lost a lot of blood. The emerald giant slowly got up, clutching his ribs in one hand. These two weren't going to give up. The monsters grappled each other, swinging each other around as the tanks and maser cannons kept attacking. Gaira managed to toss Anguirus towards the tanks and maser cannons, causing the dinosaur to fall on top of several of them. Luckily for Anguirus, his carapace absorbed any damage from landing on the vehicles. Gaira shrieked and waved his arms at the few remaining tanks that were retreating from the battlefield.

The emerald beast grabbed a battered tank from the earlier wave of vehicles that he had faced, and got down on his knees next to Anguirus. In a brutal assault, the Gargantua started pummeling his foe in the face with the heavy artillery vehicle. After a while, the Green Gargantua threw the busted tank away. Anguirus' face was bruised and bloody. The saurian was barely breathing. Gaira looked down at his fallen foe and started choking him again. Gaira shook Anguirus' head, smacking it against the ground. The giant dinosaur weakly tried to resist his foe, but he couldn't keep it up for long. Soon, he stopped moving. Anguirus was dead.

Gaira stood, bloody, battered, tired and victorious over his dead foe. The smell of blood and burnt flesh filled the air. The Green Gargantua grabbed Anguirus' corpse by the tail and dragged it into the lake, having caught a meal that would last him for days.