Well, it could be about the 10th doctor having an adventure that involves water sports. Maybe he's on a planet where water sports are a crucial part of the culture and he has to participate to solve a mystery.
There might be such a fanfic out there. However, it could be a bit hard to find as it's a rather specific combination. You could also check some Doctor Who - related fan communities where people might share or discuss fanfics like this.
One possible plot could be that during the regeneration process of the 9th Doctor, something goes awry with the Time Lord's normal regeneration cycle. Maybe there's interference from an outside force, like a powerful alien entity that wants to disrupt the natural order. This interference causes the regeneration to skip a few incarnations and directly jump to the 11th Doctor. The new 11th Doctor then has to deal with the after - effects of this abnormal regeneration. He might have some strange memories or abilities that are a mix of what the 9th Doctor was supposed to pass on and some new, unexpected elements.
The Daleks could be the main villain. They might be trying to manipulate the Doctor's regeneration to create chaos in the time - space continuum. Since the 9th Doctor's unexpected jump to the 11th Doctor disrupts the normal flow, the Daleks could take advantage of this instability to further their evil plans of universal domination.
In a fanfic, when the 10th doctor clone meets the 11th, it could be a moment full of drama. The 10th doctor clone, having his own set of memories and experiences, might initially be a bit hostile towards the 11th. But as they start to interact more, they could discover that they have more in common than they thought. For example, their love for adventure and their sense of justice. They could also compare their different TARDIS interiors and time - traveling techniques. Eventually, they might even form an alliance to protect the universe from a greater threat that neither could handle alone.
Well, perhaps the 9th Doctor and the vampire could be on a journey to find a cure for the vampire's condition. They might travel through different time periods and encounter various historical figures who have knowledge about vampires. Along the way, the Doctor tries to teach the vampire about the value of all life forms while also facing challenges from other creatures who oppose their mission.
One plot could be that an original character (oc) is a time - traveling thief who accidentally steals a crucial component from the Doctor's TARDIS. The 12th Doctor has to track this oc down across different time periods. As he does, he discovers that the oc has a tragic past that led them to a life of thievery. The Doctor decides to help the oc instead of punishing them, and together they face a threat that was awakened by the stolen component.
Well, perhaps the 10th doctor could use his TARDIS to travel to the Naruto universe. He might find Naruto as an orphan and decide to take him under his wing. He could then teach Naruto about different worlds and technologies, while also helping him with his ninja training in a very unique way, using his knowledge of science and alien cultures.
Well, perhaps the 10th Doctor could use his time - traveling abilities to go to the Naruto universe. He might find Naruto as a young orphan and decide to raise him. He could teach Naruto about different cultures and technologies from his own world, which would give Naruto an edge in his ninja training. Maybe he'd also introduce Naruto to some alien species that have similar chakra - like powers, opening up new ways for Naruto to develop his skills.
In the '10th doctor meets amy fanfic', they could start off not getting along very well. Amy might be a bit too headstrong for the Doctor at first. But as they face challenges together, like dealing with an evil alien force that's threatening the universe, they could learn to respect and rely on each other. And perhaps in the end, they become great friends who have shared memories of incredible experiences.
It could be about a character who is lost at sea and has to face various challenges alone, like fighting off sea monsters or surviving a storm.