Well, perhaps there is a rift in time and space that pulls characters from both universes together. The Assassins' skills of stealth and parkour could be combined with Kratos' brute strength. They find themselves in a strange new world that is a mix of both their own, and they have to fight their way through hordes of enemies, both Templars and creatures from God of War, to find a way back home.
One possible plot could be that Kratos, from God of War, somehow ends up in the Assassin's Creed universe. He teams up with an Assassin, perhaps Ezio. Together, they face a common enemy that threatens both their worlds. This enemy could be a powerful Templar who has acquired some of the dark magic from Kratos' world.
A cool plot could be that the Templars in the Assassin's Creed world somehow get hold of some ninjutsu scrolls. They start using these to create an army of super - soldiers. The Naruto characters then team up with the assassins to stop the Templars. Naruto could use his Rasengan against the Templars' new warriors, while Altair could use his eagle vision to spot their weaknesses. Together, they could form a unique combat strategy that combines the best of both worlds.
In a possible Assassin's Creed Watch Dogs crossover fanfiction plot, the modern - day setting of Watch Dogs is somehow intertwined with the historical conspiracy elements of Assassin's Creed. For example, the main character, a hacker, starts to receive encrypted messages that seem to be related to the Assassin's Brotherhood. As he delves deeper, he realizes that there are hidden forces at work in the city that are much older and more powerful than he thought. He then meets an Assassin who has been secretly operating in the city for years. Together, they uncover a plot that involves a powerful corporation trying to use ancient Assassin technology for their own malicious purposes. The Assassin teaches the hacker some of the ways of the Brotherhood, like how to read hidden signs in the city, and the hacker shows the Assassin how to use modern technology to their advantage.
One possible plot could be that the Assassins discover a strange and otherworldly artifact that is somehow linked to the power of Ghost Rider. The main Assassin character, perhaps Ezio or Altair, starts to have strange visions related to the Ghost Rider's world. They then have to figure out how to use or contain this power before it falls into the wrong hands, like the Templars. Along the way, they meet a character who has some connection to the Ghost Rider, like a descendant or someone who has been touched by the same dark magic.
One possible plot could be that Naruto, with his ninja skills, gets transported to the Assassin Creed world. He might team up with an Assassin, perhaps Ezio. Together, they could use Naruto's chakra - based attacks and the Assassin's stealth and combat skills to take on a common enemy, like a powerful Templar - like figure who is threatening both the ninja world and the Assassin's world.
One idea could be a crossover with Pirates of the Caribbean. The Assassin could team up with Jack Sparrow to find a hidden treasure that is also related to an ancient Piece of Eden. They'd face challenges like sea monsters and rival pirates.
One possible plot could be that the Assassins discover the wizarding world. They might team up with Harry Potter and his friends to fight against a common enemy, like a dark wizard who has ties to the Templars. The Assassins could use their skills in stealth and combat, while the wizards use magic.
Well, it could be about Darcy Lewis somehow getting involved in the Assassin's Creed world. Maybe she discovers a Piece of Eden while working on some scientific project. She could then team up with an Assassin to keep it from falling into the wrong hands.
A great plot idea for Assassin's Creed Civil War fanfiction could be to focus on the role of civilians during the war. For example, an Assassin could be protecting a group of escaped slaves who are being hunted by both Confederate soldiers and Templars. The Assassin has to use their skills not only to fight off the pursuers but also to guide the slaves to safety. This could involve exploring the Underground Railroad within the context of the Assassin - Templar conflict. Also, the fanfiction could delve into how the war is affecting the economy and how the Assassins and Templars are trying to manipulate it for their own ends. Maybe an Assassin discovers that the Templars are hoarding supplies meant for the Union army, and has to stop them.
A plot could involve Baldur being sent to the realm of God of War by Odin to spy on Kratos. However, Baldur is intrigued by Kratos' strength and his relationship with his son, Atreus. Baldur starts to question his own loyalty to Odin. Meanwhile, Kratos is suspicious of Baldur but also sees a bit of his own past self in Baldur's blind obedience to a cruel father figure. Eventually, they work together to resist Odin's control over Baldur.
A great Assassin's Creed crossover fanfiction idea is to cross it with 'Game of Thrones'. Picture an Assassin in Westeros, trying to navigate the complex web of political intrigue and assassination plots that are already rife in that world. They could be hired by different houses to carry out assassinations or be on a mission to uncover some dark secrets. Another interesting one could be a crossover with 'Cyberpunk 2077'. An Assassin in a high - tech future world, using their traditional skills along with new - age technology to take out targets in the neon - lit streets of Night City.