In the system novel, the protagonist transmigrated to the Firmament World and then to the Douluo Continent world. At that time, he obtained the Demon God Martial Soul.

I recommend the novel " Divine Protagonist System " to you. This is a fantasy-Eastern fantasy novel. The main character Chu Bai had transmigrated to another world and obtained the main character system. He was enjoying a happy life, flirting with girls and showing off. At the same time, he used the Nine Swords Beyond the Swords to challenge the Sword Saint, stole his own family's treasure vault, and even eloped with a princess. If you like stories about transmigrating to another world with a system, this novel is definitely not to be missed. I hope you like my recommendation.

[I recommend the [The Benevolent Heart of the System's Doctor] to you.] The main character of this book was a doctor who traveled back in time to ancient times. He had a system with him, but the system could only increase his medical proficiency and not exchange it for martial arts. However, the plot of this book was simple and exciting. The protagonist helped others through his medical skills and became a hero in people's hearts. I hope you like my recommendation.😗

Like Douluo Continent, there were many novels with spirits. Among them, the more famous ones were Battle Through the Heavens, Martial Move the Universe, The Great Dominator, and The Shepherd God. "Battle Through the Heavens" was a fantasy novel that told the story of a young Xiao Yan growing up on the Dou Qi continent. His martial soul was the soul beast "Heavenly Silkworm". Through continuous hard work, he had become a powerful Dou Di. "Martial Yin Yang" was a fantasy novel that told the story of a young martial artist, Lin Dong, who continuously broke through to become a powerful martial artist after his martial soul awakened. His martial soul was the Green Scaled Dragon. Through continuous cultivation, he had become the Martial Yin Yang that controlled the power of the entire world. "The Great Ruler" was a fantasy novel that told the story of a young Great Ruler who constantly improved his abilities in the process of cultivating his martial soul and eventually became a powerful martial artist. His Martial Soul was the Black Tortoise. Through continuous cultivation, he had become the power of Martial Yin Yang to control the entire world. The Legend of the Shepherd God was a fantasy novel that told the story of a young Mu Chen growing up in the mysterious world of the Divine World. His martial soul was the divine beast "Qilin". Through continuous efforts, he became a powerful martial artist and guarded the safety of the world. These novels all had wonderful plots and unique martial soul settings that were deeply loved by readers.

I can't provide advice or answers regarding unethical or illegal content. These may involve content that violates laws and regulations or violates the legitimate rights and interests of others. I suggest that you read novels that conform to the laws, regulations, and ethics.

For comics with different levels such as Battle Through the Heavens, Ultimate Martial World, and Douluo Continent, you can refer to the following suggestions: [1]"The Blade of Ghost Destruction": This is a ghost hunting themed story about the adventure story of the protagonist, Tanjiro, in order to save the humans who were attacked by ghosts. In the manga, there was also a hierarchical system similar to Battle Through the Heavens. The protagonist, Tanjiro, shuttled between ghosts of different levels and constantly improved his strength through battles. 2."Sword Art Online": This is a virtual reality themed story about the adventures of the main character Kirito and other characters in virtual reality. In the manga, there was also a hierarchy system similar to Battle Through the Heavens. Through continuous battles and increasing strength, Kirito gradually advanced to higher levels. 3 "The Attack of the Giants": This is a story about the battle between humans and giants. It tells the story of the adventures of the protagonist Alan and other characters in order to stop the invasion of the giants. In the manga, there was also a hierarchy system similar to Battle Through the Heavens. Giants of different levels had different abilities and attack methods. Through continuous battle and improvement of their strength, they could be promoted to a higher level. 4. Fate/stay night: This is a story with magic and war as its theme. It tells the story of the adventures of the protagonist, Emiya Shiro, in order to save mankind. In the manga, there was also a hierarchy system similar to Battle Through the Heavens. Followers of different levels had different abilities and characteristics. Through continuous combat and improving their strength, they could advance to a higher level. The above are some manga recommendations similar to Battle Through the Heavens, Martial Extreme World, Douluo Continent, etc. I hope they can be of help.

The system novels that transmigrated to Douluo Continent were recommended as follows: "Douluo Continent" series of novels: This is one of the representative works of the Tang family's three young masters. It tells the story of a soul master's world protagonist who continuously improves his strength by obtaining soul rings and soul power, and finally defeats the evil forces. 2 "Douluo Continent's Eternal Soul Master": This is a derivative novel of the "Douluo Continent" series. The protagonist is a system flow soul master who gradually grows into a powerful soul master by completing missions and improving his soul power. 3 "Douluo Continent's Peerless Tang Sect": This is a derivative novel of the "Douluo Continent" series. It narrates the story of a genius soul master. The main character continuously improves his strength by obtaining soul rings and soul power, and eventually becomes a legendary figure on the Douluo Continent. 4 "Douluo Continent's Spirit Master": This is a derivative novel of the "Douluo Continent" series. The main character is a system flow Spirit Master who unceasingly raises his spirit ability by completing missions and spirit power elevation, finally becoming a top spirit master. 5 "Douluo Continent's Legend of Soul Masters": This is a derivative novel of the "Douluo Continent" series. It narrates the story of a Soul Master's world protagonist who continuously improves his strength by obtaining soul rings and soul power, and finally becomes a legendary Soul Master.

The Douluo Continent's Ancient Martial Soul was a novel with a soul master as the main character. It told the story of the main character, Tang Wulin, searching for soul beasts on the Douluo Continent and cultivating his soul power. Tang Wulin was a soul master with extraordinary talent. He possessed the soul power of three soul rings and dreamed of becoming a powerful soul master. In order to achieve this goal, he embarked on the path of searching for soul beasts and met many like-minded people in the process. On his journey, he encountered an ancient spirit, a mysterious spirit beast with powerful spirit abilities. The ancient martial soul bestowed Tang Wulin with powerful offensive and defensive abilities, making him an outstanding combat soul master. Tang Wulin and his ancient martial soul had experienced many adventures together. They had defeated many soul beasts and engaged in fierce battles with other soul masters. During this process, Tang Wulin grew and improved his abilities continuously until he became a powerful soul master and protected the Douluo Continent.

The protagonist's martial soul is the forbidden martial soul of the continent he is from. For fantasy novels with Buddhist martial souls, you can refer to the following examples: "Spirit" was a fantasy novel that described the growth of a young martial artist. The main character had a forbidden martial soul, the Buddhist martial soul. Because this kind of martial soul was regarded as an evil existence on the continent, the protagonist's family had once abandoned him. However, through continuous efforts and adventures, he finally became a great martial artist. As the protagonist grew up, he encountered many difficulties and challenges, including confrontations with other spirits, conflicts between families, and disputes between countries. Through his wisdom and strength, he gradually overcame these difficulties and eventually became a legendary figure. This novel was full of fantasy, full of elements such as battle, adventure, love and friendship, and was very popular among readers.

😋I recommend the following novels to you: 1. "Naruto's Calabash Brothers Legacy": After the protagonist transmigrated to the Naruto World, he obtained the legacy of the Calabash Brothers, surpassing the Calabash Brothers in the anime and becoming the God of Ninja. 2. "Naruto: Uchiha Ape: The main character is reborn into the Ape Clan. He possesses the Sharunan. There is no external power system, but it is full of mischief. 3. "Naruto: My Ninjutsu is Blackened": The protagonist transmigrated to the Naruto World and was bound to the Blackening System, so that the ninjutsu and blood that he learned were all blackened, and he became a supreme master. I hope you like my recommendation. Muah ~

😋I recommend the novel, The Peak of Mentor's Doctrine, to you. Because of a thread-bound "Martial Code", the protagonist transmigrated to the primitive continent. He trained his disciples in a world full of cruelty and slaughter. He defeated powerful enemies and reached the peak. This martial code was also the first martial code in that world. I hope you like this fairy's recommendation. Muah ~😗