Ren and his comrades successfully cleared the Wave of another country, and then headed to the town the Spirit Turtle was sleeping in to search for greater strength.
Thinking of his game, and what happened in Update: Episode 7, The Assault of the Spirit Turtle. According to Ren, the Spirit Turtle was going to be the mastermind behind an even greater calamity, so it was best to kill him off early. In the near future, a plague would have struck that land. The people would fall one after the other, and the cause of that would be the Spirit Turtle. He would manipulate their corpses and create an undead army with his powers of mind control. Apparently, in the games Ren played, if he didn't act fast a large calamity would befall this land. This event was big enough in scale to cause the fall of nations and the formation of several counter-measure organizations. That’s why Ren’s main goal was the prevention of this disaster. The boss was supposed to be beatable at level 60. Since Ren was over 80, he thought it wouldn't be difficult.
The reason he acted without the country’s consent was that in the game he played, the Turtle’s mind control was affecting the actions of the leaders of countries as well. It seems that it was being treated as a sort of quest. And that’s why negotiations were pointless.
Ren infiltrated a temple slightly outside of the village. Ren's actions were questioned by his party. He explained to them the monster sleeping there had already infiltrated the upper echelon of government and sitting around and waiting for negotiations to finish is pointless. A monk then asked who they were, as he was about to destroy the statue that would awaken the turtle, a group of monks surrounded him. Because they had appeared in the basement of an abandoned temple, Ren was able to conclude that they were under the Turtle’s influence. And destroyed the statue. Ren’s comrades assisted in the destruction of the statue. The monks shouted and raised their weapons. The monks then realized that Ren was the Hero of the Sword. Ren then explained that he was there to vanquish the darkness that sleeps beneath these lands. As they were saying that, the ground begins to rumble beneath them. Ren carefully knocked the monks out and ran in the direction of the rumbling sound.
With confidence, Ren rushed towards the Turtle. While closing in, he thought he saw someone use a skill on the head, but he just assumed it was one of the adventurers fighting it. Thinking that this world’s adventurers wouldn't be enough, Ren raised his sword towards the Turtle. He used「Handlet Sword!」, however, it’s a skill that takes a while to activate. So he stacked on another attack,「Thunder Blade!」. But, the Spirit Turtle was largely unaffected. Ren felt something was off, but he kept fighting. Without giving up, he fought for the people in danger of the beast.
After being defeated, when he was aware of his situation, The Spirit Turtle was already walking away without paying him any mind. Ren was surrounded by the corpses of his comrades. They were cruelly mangled bodies. Destroyed so badly even Ren couldn't identify them. The only thing he could understand was that his party members were all dead.
Ren’s brain could not comprehend the events that had just happened. And Ren’s mind shut down for a period of time. He prayed for the slight chance that, like a game, he would be able to revive them. But no gods would hear his wish, and Ren understood that from the beginning.
After that, Ren rushed through the swarm of Spirit Turtle Familiars, and tried to save as many people as he could, but he eventually lost consciousness. When he regained consciousness, the Spirit Turtle’s reign of terror had already ended.