One way is to check on popular fanfiction websites. Look for ones with high ratings and a lot of reviews. For example, Archive of Our Own (AO3) has a large collection of AOT fanfictions. You can search for the most popular ones there.
Another difference lies in the overall mood. Canon AOT has a rather dark, gritty, and often hopeless mood due to the constant threat of Titans. However, a friendly Titan fanfic would likely have a more positive, hopeful mood. It might explore themes of redemption for the Titans, or how their existence could be beneficial to the world of AOT. This is a complete departure from the doom - and - gloom feeling that often pervades the official AOT story.
" I don't think it'll necessarily meet your needs, but I'll try my best to recommend a novel that's most relevant to your description." The book, Super Demon Absorber, is a fantasy novel written by a baby-faced author. The general plot of this novel is as follows:
"Hmm? There was demonic qi! Watch my demon subduing divine power!" "Woof woof…" How could it be a dog! I must have opened it wrong! Again!" "Demon Subduing Divine Ability! Suck, suck, suck!" You have subdued a Flame Demon, obtained a Flame Talisman, subdued a Barbarian Demon, obtained a Strength Talisman, subdued a Shadow Demon, obtained a Shadow Talisman…There's demonic qi again!" "Hehehe! Little demon, don't run!"
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" Wilderness: I Can Clone Thousands of Magic Weapons " was a Xianxia, Mythological, and Cultivation novel written by the author, Yanyu Xingzhou. The general plot of this novel was:
The soul of the Earth had transmigrated to the time before the Witchcraft Cataclysm and became the eldest disciple of the Supreme Pure Daoist Heavenspan, the Treasure Daoist, who had awakened the golden finger of the magic treasure replication system.
From then on, the number of 3,000 Connate Numinous treasures in the Primordial World was broken.
"Little Li Flying Dagger" or "Immortal Slaying Flying Dagger", who was more powerful?
The Communication Talisman could allow long-distance video calls!
The Infinite Gloves had endless potential!
The Hextech Gun was once again showing off!
'A Brick' specialized in curing all kinds of unconvinced people!
The Death God Scythe, the Ghost Extinguishing Blade, the Peacock Plume, and other interesting Numinous Treasures appeared one after another.
This is a more lively and interesting primeval world, but also a primeval world full of secrets. I look forward to entering this legendary mysterious era with you.
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" Ghosts and Demons Are Myself " was a novel written by the author, Jianshui II. It was a suspense-themed novel. The general plot of the novel was:
[You have obtained the ability to mystify everything.] [You have Mysticalized a copper coin. You can use it to buy anything.] " You've made a tree mysterious, and all the trees within a hundred miles have become your eyes and ears. You have mysteriously turned into a bow that can shoot anything you see. [You have made a stone sculpture a mystery. It has come alive and will break your neck when you are unprepared…] [You have mysteriously transformed a Starbeck. The Starbeck broke out of the ground and ran towards you while screaming in embarrassment…] [You dodged Starbeck's pursuit and turned your attention to the cultivation technique…] [You have mysticalized a cultivation technique. You have obtained a mysterious cultivation technique that is not cultivated by humans,[Hungry Ghost Dao].] [You have mysticized [Hungry Ghost Path] and obtained [Six Paths of Reincarnation].] [You have mysticized the [Six Paths of Reincarnation] and obtained the [Divine Realm].] You keep on being mysterious... Until one day, you heard a sentence from a passerby. "Mysterious World, the server is open today!" You:
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Divine Ghost Sword was a fantasy novel written by Emperor Demon. The general plot of this novel was:
Mateng brought the Ghostblade skill to the Other World. Was he useless? Powerful enemy? In front of the full-time Ghost Sword, they were nothing! Experts from another world should be prepared to receive his whipping. He also had a super divine artifact, the Spirit Rhinoceros Ring, to accompany him. As long as his strength increased, the ring would be given to him! What kind of changes would a transmigrator with Ghostblade skills bring to this world?
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The Legend of the Mirror Demon was a Xianxia-Cultivation novel written by the author, Ling. The general plot of the novel was:
His soul broke through the void, transmigrated to another world, and attached itself to a mirror. From then on, he embarked on the long path of demonic cultivation.
A mirror that could talk? A spiritual treasure? Magic tool? Or a big demon? Mirrors could also cultivate into demons?
The mirror was all-encompassing, and its illusions were divine, allowing it to roam the nine heavens.
With the soul of a human, the body of a mirror, and the dignity of a great demon, he galloped through the cultivation world and wrote the legend of a heavenly demon.
According to the records of the Ten Thousand Demon Divine Sea,"Mirror Demon Yi Chen is the Heaven Defying Bead. It absorbs the essence of the sun and moon to become a demon. It can change into thousands of forms. It is the leader of the mirror, flower, water, and moon demons!"
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" I Have a Monster Editor " was a fantasy novel written by the author, the King of Flames. The general plot of the novel was:
Hell was empty, and evil spirits were in the human world! In this time of national turmoil and the emergence of evildoers, we righteous people should…Wait, I seem to be the Lord of Demons and Monsters, the King of Demons and Monsters? Qin Hao brought along the Strange Editor System and created vampires, evil dragons, deer-headed spirits, and other monsters in this foreign world where bones were everywhere and monsters were everywhere. He used monsters to subdue monsters!。
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" Weird: I Have a Cheater " was a fantasy immortal cultivation novel written by the author Xiao Ah. The general plot of this novel was:
It was said that there were countless heavenly passages outside the human world, where countless gods lived. It was called the Great Void.
Tang Xuan brought a cheat device and transmigrated here. At the start of the game, he was entangled by the evil god while cultivating the Wild Dao Scripture in the mountain temple.
Fortunately, the cheating device allowed him to study cultivation techniques.
Mo Luo Yin Written Charm Scripture.
Obtained three evolution paths: Crow's Eye, Flesh, and Mutation.
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" Demon God of War " was a fantasy novel written by the author, I Am Ugly to the Deep of My Soul. The general plot of this novel was:
In the ancient barbaric era, demons wreaked havoc on the earth…
The human sages of the earth had created thousands of martial arts to fight against them…
After that, there were people who were smarter than the heavens. They collected the demon blood, purified it, and refined it with countless spiritual herbs. They found human martial artists with special bloodlines and implanted the demon blood into them, allowing them to transform into demons while retaining their human characteristics...
Such martial artists were known as 'Demon Warriors.' They possessed destructive power that even demons could not hope to match, and they had endless potential. His fist could shatter stars, his palm could break rivers, the sun and moon could go through the sky, and his roar could fall stars…
There were many kinds of demon bloodlines. Therefore, demon warriors could transform into birds and eagles, soaring in the sky. Some could become the essence of beasts, with strong claws and sharp teeth…Some could even transform into Primordial Fierce Beasts, which could create destructive storms with a flap of their wings. They could summon lightning, ice, and snow. They could also absorb the starlight of the sun, moon, and stars. Their lives were almost eternal, and they could coexist with the world…
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Servants of Magical Treasures was a novel written by the author, Yama Wuying, about a mysterious world. The general plot of the novel was:
The opening umbrella is said to be a magical treasure, but who can tell me why it's full of holes? It was fine if it was full of holes, but why did someone always want to use magic treasures to cause trouble? It's fine if you're causing trouble, but why do you always let me handle it? As an otaku, I just want to confess to my goddess. Who can tell me what to do? Speaking of which…mysterious magic treasures possessed all kinds of incredible powers. The world was also changing. Should I cause trouble too? Why don't I just hug his thigh…
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Suppress Evil was a mystery novel written by the author, Instant Blue Absorption. The general plot of this novel was:
In addition to the Taoist priests who vanquished demons and devils, the wizards with strange methods, and the corpse drivers who were both righteous and evil, there were also the Evil Suppressors. The Dragon Slaying Sword under the bridge in the small village, the Shi Gandang who was hired with a large sum of money, the gourd and the Bagua mirror in the ancient house in the deep mountains, and the butcher knife hanging in the haunted house were all left behind by the Evil Suppressors…
I'm not sure exactly, but there are quite a few volumes of the Attack on Titan manga. You might want to check reliable sources or the official publisher for the precise count.