Well, it could lead to some really wild adventures. Harry could use the TARDIS to travel through time and space, perhaps going back in time to change certain events in the wizarding world. He might also use it to explore different magical realms that are far beyond what he could reach with his broomstick or normal magic.
I haven't actually read this fanfic. But generally, it might be about Harry from the Harry Potter universe building a TARDIS which is from Doctor Who. It could involve him using his magic skills to construct this time - and - space - traveling device. Maybe he combines spells from Hogwarts with the technology (in a magical way) of the TARDIS.
Yes, there are likely some fanfictions out there with this concept. Fanfiction writers often come up with creative crossovers, and combining the magical world of Harry Potter with the time - and - space - traveling TARDIS from Doctor Who is a really interesting idea that some fans might have explored in their writing.
The concept of time is also treated differently in this type of fanfiction. While the Time - Turner in Harry Potter allows for a limited form of time travel, the TARDIS can travel through all of time and space. Fanfiction writers often explore how these two different time - traveling mechanisms interact. They might have the TARDIS enhance the power of the Time - Turner or use the Time - Turner to fix a problem within the TARDIS's time - space continuum. This exploration of time adds a whole new layer of complexity and uniqueness to the stories.
Maybe he discovers some ancient magical - technological hybrid plans. He could find them in a hidden part of the Hogwarts library or in an old wizard's lair. Then, with his knowledge of magic and his friends' help, he starts to piece together the parts, using magic to substitute for some of the more advanced technological components that are hard to come by in the wizarding world.
Well, Harry Potter's loyalty and friendship values could play a big role. Just like he has his friends in Hogwarts, he could form new friendships during his TARDIS adventures. His ability to face challenges head - on, which is a big part of his Gryffindor nature, would also be important. He might face challenges like dealing with time - paradoxes or hostile alien species. His knowledge of the wizarding world's history could also be relevant. For instance, if the TARDIS takes him to a time related to a magical event in the wizarding world's past, he could use his knowledge to make sense of the situation and perhaps even change things for the better.
It could be amazing. Harry might use the TARDIS to travel to different magical places in time and space. He could visit ancient magical civilizations or go to the future to see how magic has evolved. Maybe he'd take his friends along and they'd have all sorts of adventures that combine the magic from Harry Potter and the technology (sort of) of the TARDIS.
Hermione would be a great help. Her vast knowledge of magic and books could provide the necessary information for building the planet, like the right spells and magical theories.
Dumbledore might help in a spiritual or advisory way. Even though he's passed away, his wisdom could be passed on through memories or some magical means. Also, Hagrid could be a great help. He could assist in building areas suitable for magical creatures with his love and understanding of them.