One possible storyline could be a character from Dark Souls, like the Chosen Undead, finding themselves in the world of Game of Thrones. They might use their combat skills to survive in the brutal political and war - filled environment of Westeros. For example, facing off against the White Walkers with their unique Dark Souls weaponry.
The Ashen One would be really interesting. They are a resilient and battle - hardened character. In Game of Thrones, they would be like a mysterious force. Their combat skills and ability to face all kinds of terrifying enemies in Dark Souls would make them a formidable presence in the political and war - torn landscape of Westeros. They could potentially be a wild card in the power struggles between the houses.
Another approach could be to merge the magic systems. In Dark Souls, there are different types of magic like pyromancy and sorcery. Imagine if these were introduced into the Game of Thrones world. Maybe a pyromancer could influence the outcome of battles in Westeros in a new and unexpected way, or a sorcerer could use their illusions to deceive the power - hungry lords and ladies.
The characters from Dark Souls are used to a world full of danger and death around every corner. In Game of Thrones, they would likely find the political intrigue and backstabbing to be just as dangerous as any monster. For example, a Dark Souls knight might initially be confused by the complex web of alliances and betrayals in Westeros but would soon learn to navigate it with their combat - hardened instincts.
A plot could revolve around a dragon in Game of Thrones having similar characteristics to the dragons in Dark Souls. Maybe the Night King has some connection to the Abyss from Dark Souls. A character from Dark Souls could team up with Jon Snow to fight against the White Walkers. The Dark Souls character could introduce new ways of forging weapons and armor that are far more advanced than what is known in Westeros, giving the good guys an edge in the fight.
Dark Souls has a deep lore regarding ancient and powerful artifacts. In a Game of Thrones fanfic, these could be translated into powerful weapons or items. For example, a sword that has the power to drain the life force of its enemies, similar to some weapons in Dark Souls. This would change the dynamics of battles and political intrigue in the Seven Kingdoms as characters would seek these powerful artifacts to gain an advantage.
To write a great 'Dark Souls 3 Crossover Fanfiction', you need to be creative with the settings. If you're crossing it with something like the Lord of the Rings, how will Middle - earth and Lothric co - exist? You also have to develop the characters well. Let them grow and change as they experience the new world. And use the unique elements of both universes. Maybe combine the One Ring's power with a Dark Souls 3 artifact. This will make your fanfiction stand out.
A possible fanfiction could involve the creation of a new magic system in Westeros that combines the dark and mysterious nature of the Rinnegan with the existing magic in 'Game of Thrones'. For example, the White Walkers could be somehow related to the Rinnegan powers. Maybe the Night King was once a normal man who was experimented on with Rinnegan - inspired magic, which turned him into the powerful and terrifying being he is now. This would add a whole new layer of mystery and danger to the fight against the White Walkers.
One idea could be a crossover with 'The Lord of the Rings'. Picture the Dark Souls characters in Middle - earth, facing off against orcs and other dark creatures. Another could be a crossover with 'Bloodborne'. The gothic and nightmarish settings of both could blend well, with hunters and Dark Souls' warriors teaming up against a greater evil. A third idea might be a crossover with 'Final Fantasy'. The different magic systems and character classes could create really unique and exciting storylines.
A crossover with 'Final Fantasy' would be cool. The magic systems in both could be combined in interesting ways. For example, a Dark Souls 2 mage could learn some spells from a Final Fantasy character. Also, a crossover with 'The Elder Scrolls' series. The vast open worlds of both could create an amazing setting for the fanfiction. The character could explore different regions of Tamriel and use their Dark Souls 2 abilities to survive.