A possible plot is that Conan is brought to Middle - earth by a powerful magic accident. He lands in the Shire and is initially confused by the hobbits' way of life. But when he learns about the threat of Sauron, he decides to help. He teams up with Aragorn and they form an unlikely duo. Conan's no - nonsense attitude and Aragorn's leadership skills complement each other as they lead an army against Sauron's forces.
Conan and Gandalf would make an interesting pair. Gandalf has his magic and wisdom, while Conan has his raw strength. They could have some great exchanges. For instance, Gandalf could be trying to guide Conan in understanding the more complex politics and magic of Middle - earth, while Conan could be impatient and just want to get to the fighting. Their different approaches to problem - solving would create an interesting dynamic.
One idea could be that the One Ring somehow ends up in the world of Pirates of the Caribbean. Jack Sparrow, being the wily character he is, gets wind of its power and decides to either use it for his own gain or sell it to the highest bidder. The Fellowship, in turn, has to track it down in this strange new world full of pirates, sea monsters, and cursed treasures.
Definitely Legolas and Will Turner. Legolas with his amazing archery skills could teach Will some new techniques, and Will could show Legolas the ropes of being a pirate. They both have a sense of honor and loyalty, so they would make an interesting duo.
A lesser - known but excellent piece is 'Ringbearer Buffy'. Here, Buffy is somehow made into a ringbearer. It's a unique take on both franchises. The story delves deep into how Buffy's personality and her experiences as a slayer would affect her role in the quest to destroy the One Ring. It has some great character development and some really intense action scenes.
In a Harry Potter and LOTR crossover fanfiction, black magic could take on different forms. In the Harry Potter universe, it's often associated with the Dark Arts like the Unforgivable Curses. In LOTR, dark magic is related to Sauron and his minions. A crossover might explore how wizards from Harry Potter's world react to the more ancient and malevolent black magic of Middle - earth.
Sesshomaru's speed and agility would be a great asset in Middle - earth. He could easily outrun orcs and other foes. His sword, Tenseiga, which has the power to resurrect, could also have an interesting impact. For example, if he were to use it on a fallen hero, it could change the course of a battle.
The main appeal is the combination of two very different but beloved universes. Buffy's world is modern, full of vampires and demons, while LotR is a high - fantasy epic. When they cross over, it creates a whole new set of possibilities. For example, seeing Buffy fight Orcs or Aragorn dealing with vampires is really exciting.
One way to blend the themes is through the idea of sacrifice. In LOTR, many characters sacrifice for the greater good, like Boromir. In Narnia, Aslan sacrifices himself. A fanfiction could explore how characters from both worlds understand and are affected by sacrifice. Also, the theme of the power of nature is present in both. The ents in LOTR and the talking animals and plants in Narnia can be part of a story that shows how nature can be a force for good against the encroaching evil in both worlds.
The appeal lies in the combination of two very rich and beloved fictional universes. Fans of both 'The Lord of the Rings' and 'Eragon' get to see their favorite elements come together. It's like a dream come true for many, seeing Aragorn interact with Eragon, for instance.