I have a wildlife zoo - Chapter 202 Awarding Prizes

After crossing over to Naruto World, Shiranui Yuuji found that there was an incomparably terrifying Godzilla in his body.

“You are Tailless Bijuu? Your chakra is astonishing…. What a coincidence, so am I.”

“You know Bijuu’s coat? I don’t have Bijuu’s coat, but I do have Godzilla Coat-”

“Bijuudama is terrifying!! It can destroy a mountain as soon as he sends it down?”

Hiss, that Bijuudama scared Yuuji, he quickly moved his hands to form seals,

“Nuclear Release – Atomic Breath!”

When Yuuji turned into Red lotus form, Godzilla pressed Nine-Tailed to the ground.

“Nine-Tailed, your strength is too strong. You need to be fried…”

Nine-Tailed, “?”

“What Jinchuriki are you exactly?”

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates

In novels with a stud there is always a Senior Martial Brother like this:

In the early stages of the novel, his innate talent is high, his cultivation is good, his appearance is handsome, and he has an intelligent, cute younger Martial Sister as a fiancée.

In the middle stages of the novel, he is caught unprepared and defeated by a young disciple (the protagonist) in the sect who’s hardly remarkable at all. From then on, he falls from his godly altar and loses his brilliance. Even his young Martial Sister leaves him for someone else.

In the late stages of the novel, he continues to turn dark, going down the Demonic Path and becoming the major villainous boss. However, the protagonist still ruthlessly defeats him and his soul is eternally sealed.

Once Qin Mo opened his eyes, he discovered that he had become this Senior Martial Brother.

- Description from Novelupdates

He was supposed to transmigrate to a magic world, but due to an accident, he ended up trapped in a massive library. The system assigned him a task: for every book he read, he would be rewarded with mana stones, until he finished reading all the books. A trillion years later, Daniel finally finished the last book! [Ding, detecting that the host has finished the final book. Calculating system rewards.] [Ding, reward calculation complete. Dispatching rewards. The total number of mana stones the host has accumulated: 99999999...9999.] “Damn, am I that rich now?” [Ding, detecting that the host has completed the task. Loading world...] ... Goddess of Fate: “Daniel, my divine realm needs expansion. Could you sponsor me with some mana stones?” God of Storm: “Daniel, the divine punishment is about to descend. Could you lend me some power to help me get through it?”