Well, Dumbledore from Harry Potter is extremely powerful with his vast knowledge of magic. However, Splinter from Ninja Turtles is a very wise and skilled master. If they were to face off in a strategic battle, it would be a close call. But considering Dumbledore can perform powerful spells like the Patronus Charm and can manipulate time with the Time - Turner, he might be more powerful in a more general sense. But Splinter's ability to train the turtles to be such great fighters shouldn't be underestimated.
Dumbledore would be a strong contender. He has great wisdom and powerful magic. However, Maleficent's magic is more primal and based on fairy - tale rules. If they were to face off, Dumbledore's experience and knowledge of different magics might give him an edge, but Maleficent's unpredictable nature could also make her a formidable opponent. For instance, if they were in a battle of wills, Dumbledore's calm and collected nature might be pitted against Maleficent's vengeful and proud attitude.
The Cortez parents from Spy Kids could also be very powerful in this crossover. They are experienced spies with a lot of skills and knowledge. In a fanfiction, they could learn magic quickly and use their spy tactics along with magic. They could be a threat to the dark wizards in Harry Potter as they are used to dealing with dangerous foes in their own world. Their combination of spy skills and new - found magic could make them one of the most powerful entities in this crossover scenario.
Leonardo is often very popular. He's the leader, so fanfictions might focus on his leadership challenges and how he makes decisions for the team.
I think it would be Dumbledore. He is extremely powerful in the Harry Potter world. His wisdom and magical abilities are off the charts. In Westeros, he could use his powerful spells to influence events, protect people from danger, and perhaps even find a way to bring peace to the war - torn land. His ability to see into people's minds would also give him an edge in the political games of Westeros.
One interesting crossover could be the turtles using their ninja skills to help the Hogwarts students during a big battle at the school. Maybe they teach the students some self - defense moves that wizards don't usually have.
Leonardo is often popular. In human fanfiction, he might be depicted as a strong and noble leader even in human form, guiding the other turtles and any human allies. He could be the one who tries to uphold justice in a human world.
It's really hard to say. Percy has his demigod powers which are extremely strong. He can control water, heal himself in water, and has great combat skills. But Harry has magic, which can do a vast array of things from simple spells to powerful dark magic counter - spells. In a one - on - one fight, it might depend on the environment. If it's near water, Percy would have an advantage. But if it's in a magical fortress like Hogwarts, Harry might be able to use the environment to his benefit.
In a fanfiction where Harry Potter meets the Charmed Ones, determining who is more powerful is complex. Harry has shown great courage and skill in the wizarding world. His Patronus charm, for instance, is a powerful form of magic. He also has the support of his friends and the entire wizarding community in times of need. The Charmed Ones, on the other hand, have a unique set of powers that are more related to their family heritage. They can vanquish demons and have a deep connection to their Book of Shadows. If it comes to a direct confrontation, it might seem that Harry's offensive spells like the Killing Curse (although he would never use it unjustly) are very powerful. But the Charmed Ones' ability to work together and their diverse powers like premonition and molecular combustion could give them an advantage. It really depends on how the author of the fanfiction wants to portray their encounter and the rules they set for the use of magic.
Klaus Mikaelson might also be considered the most powerful. His hybrid status gives him super strength, speed, and the ability to compel others. In the world of Game of Thrones, he could easily use his compulsion on many of the characters to get what he wants. He's also very difficult to kill, which would give him an edge over most characters from Game of Thrones.
It's hard to say, but Tsuna with his Dying Will Mode might be a strong contender. He has enhanced strength and speed, and if he could also use magic from the Harry Potter world, he could be extremely powerful. However, Voldemort with his dark magic skills and his army of Death Eaters would also be a force to be reckoned with.