17 Power of Ten » by thewhitewolf1412 While on a camping trip with his family, five year old Harry stumbles upon an otherworldly device that grants him the power to transform into different alien life-forms. Along with a wise-cracking alien companion, Harry takes the Wizarding world by storm with his power. Watch as he becomes a hero, or dies trying. Don't own Harry Potter or Ben 10
T, English, Humor & Adventure, chapters: 3, words: 3k+, favs: 129, follows: 145, updated: 4/7 published: 9/2/2018
4 Harry Tennyson hatchlings oneshot by ReadAlert Just a thought about Omnitrix wielding Harry Potter laying eggs as Big Chill violated the conditions to a magical Binding Contract between him and Ginny. Contains male pregnancy, Harry/Gwen/Female!Kevin pairing, Dumbledore bashing.
T, English, Sci-Fi & Family, words: 8k+, favs: 17, follows: 15, 2/15, [Harry P., Gwen T., Kevin] Albus D.
The-Boy-Who-Battles-The-Stars (Cancelled) » by Bill is King believer What are Prophecies? A prophecy is a prediction made by a Seer, who can see into the future, they are made in the form of a cryptic language that does not allow direct interpretation. Prophecies often hold great importance, They may go to great lengths to ensure that it comes true (Dumbledore) or take great pains to avoid it (Tom Riddle) even when they not apart of the Prophecy.
T, English, Fantasy & Sci-Fi, chapters: 2, words: 2k+, favs: 7, follows: 4, updated: 7/15/2020 published: 7/13/2020
35 The Lightning Ultimatrix » by The True Writer. Zerthin This is another crossover that my brain has created; This crossover will ask the question. Can Harry Potter be the Wielder of the Ultimatrix, can he handle hyper-evolved creatures of magic and aliens? Can Harry belong in Slytherin? These are the questions that this story will answer I hope you enjoy. Also, it's slash! Pairing: Harry/?
K+, English, Romance & Adventure, chapters: 9, words: 10k+, favs: 137, follows: 139, updated: 11/7/2019 published: 11/8/2017
89 The Potter and the Tennysons: Families of 10 » by Watch Seeker Harry Potter's wish was simple; he wants a true family to care him, comfort him, and love him. And there was another; he wants a friend. And they all became true. Only, the new family is full of warriors, and his new friend can turn into aliens and became his BROTHER!
T, English, Adventure & Family, chapters: 8, words: 90k+, favs: 271, follows: 297, updated: 12/1/2018 published: 1/16/2017, Harry P., Ben T., Gwen T., Max T.
8 Penpals » by Lambdadelta of the Absolute Five months after Voldemort's defeat, Hermione breaks up with Ron and gets a letter from her American pen pal Gwen. HP/HG all the way! Post Deathly Hallows, no epilogue.
T, English, Drama & Friendship, chapters: 5, words: 3k+, favs: 28, follows: 33, updated: 8/31/2018 published: 5/15/2014, Hermione G., Gwen T.
17 Ben Tennyson and The Chamber of Secrets » by OlivertomixOO7 After forcing Albedo to give him Ultimatrix and surviving a deadly attack from Vilgax Ben receives a letter from the Hogwarts school of Witchcraft and Sorcery.But he is forced to study in second year with children who are quite younger than him. Over the top of all that an ancient creature is hunting down the students. Can Ben save the day in the end or he will end up as a victim?
T, English, chapters: 3, words: 7k+, favs: 30, follows: 40, updated: 8/13/2018 published: 6/23/2017
36 A Plumber Amongst Wizards » by OlivertomixOO7 Ben Tennyson had been through it all. Vicious Alien warlords, Powerful Warlocks, Zombies, Ghosts and a lots of craziness. He conquered it all with the help of his allies and his ever trusted watch. However he didn't expect to get thrown in the war going on in British Wizarding world while visiting her mother's cousin Petunia. Will he manage to save the day? Or He will fail?
T, English, chapters: 5, words: 16k+, favs: 99, follows: 130, updated: 1/31/2018 published: 6/18/2017
9 The Two Anodites That Are Partners » by Sphintusfan01 Harry and hermioneare born as anodites, when the two of them were going to use the time turner to travel back in time to save Sirius the time turner overloaded and sent them into the Ben 10 universe.
T, English, Adventure, chapters: 2, words: 2k+, favs: 40, follows: 52, updated: 2/3/2017 published: 2/1/2017, Harry P., Hermione G.
167 Harry Potter Multi Crossover » by magical fan18 Harry gets the Omnitrix at a young age, possibly around 7 years old while living with the Dursley's and with it he takes control of his own life, becomes his own person who will stand up for what is right and will get help along the way by known heroes of DC and some extra Characters added in, OC'S INCLUDED.
T, English, Adventure & Sci-Fi, chapters: 13, words: 71k+, favs: 692, follows: 697, updated: 1/28/2017 published: 2/3/2012, Harry P.
33 The Tetramand Prince by Gamer95 Looma Redwind returns to Earth, looking for her fiance. However, she ends up making a miscalculation, and finds herself in England, where she meets a little boy that changes her outlook on life...
T, English, Family & Hurt/Comfort, words: 3k+, favs: 210, follows: 214, 8/24/2016, Harry P., Princess Looma
24 Harry 10,000 by God of the Challenge After Voldemort's defeat, James and Lilly praise their son, Edward, but leave Harry with the Dursleys. He is eventually rescued, and vows to show those that caused him so much pain and suffering, what true power means.
T, English, Adventure, words: 1k+, favs: 151, follows: 167, 10/26/2015, Harry P.
14 Harrzarro by God of the Challenge After putting up with his parents neglect, Harry Potter leaves his home, planning to make a name for himself, away from those who treated him so cruelly. The same day, he finds Benzarro's omnitrix, a Macanivore named Chunky, and an Indian Python named Kaa. With the omnitrix in hand, Harry and his new friends begin their journey.
T, English, Adventure, words: 2k+, favs: 111, follows: 114, 9/23/2015, Harry P.
7 Janet Harker and an Adventure with Aliens » by Nerdfighter1309 A spin-off from my other stories starting 'Janet Harker and the Philosopher's Stone', so this is also a minor crossover with Percy Jackson and the Olympians. Auror Thom Harker and his daughter Janet go to protect an artifact in Bellwood, what could go wrong?
K+, English, Adventure & Sci-Fi, chapters: 9, words: 13k+, favs: 3, follows: 4, updated: 9/9/2015 published: 8/31/2015
3 order of the phoenix Rewrite » by diamondholder ben Tennyson saves Albus Dumbledore from a couple of death eaters and gets offered a job and that is to keep harry potter safe from possible death eater attacks. the main paring will be BenXGinny the secondary pairing will be HarryxHerimone.
T, English, Romance, chapters: 4, words: 4k+, favs: 13, follows: 13, updated: 5/28/2015 published: 5/17/2015, Harry P., Ginny W., Ben T., Gwen T.
56 The Wizard Bearer » by KingOuma During the summer before his tenth birthday, the Dursleys decide on a picnic day out in the country, taking Harry with them. Unknown to them a gift from the heavens that was to crash across the pond makes it way towards them instead. Now with the power of magic and advanced technology the future set upon Harry changes forever.
T, English, Adventure, chapters: 5, words: 40k+, favs: 310, follows: 384, updated: 5/24/2015 published: 7/21/2014, Harry P., Hermione G., Draco M., Neville L.
20 Harry Potter and the Magitrix by NextGenPokemon After being selected for the tournament Harry goes outside instead of the common room. And as he sits worrying he gains a powerful weapon for the future... The Magitrix.
T, English, Adventure & Romance, words: 1k+, favs: 112, follows: 147, 7/15/2014, [Harry P., Fleur D.]
64 Where The Magic Happens » by Promise10 If a Dark Lord with eons of experience attacks you, maybe what you need is an extraterrestrial ally. When Ben Tennyson arrives and saves Harry from Voldemort in the graveyard, the magical world is shocked. Now, with Ben's help, can Harry become the Hero he was meant to be? AU
T, English, Adventure & Romance, chapters: 5, words: 17k+, favs: 116, follows: 122, updated: 4/8/2014 published: 2/15/2014, [Harry P., Hermione G.] [Ben T., Luna L.]
2 HarryPotterBen 10 crossover challenge by pokemondemon013 Hi please come and try this challenge and I forgot to write this in. The story can be any rating as long as you mark it right . I don't own Harry Potter or Ben 10 I would love to but I don't so please don't complain this is my first try on this. Review if you like my idea.
K+, English, words: 164, favs: 2, follows: 2, 7/27/2013
2 Back To School » by cjsmalley An old piece of mine.
T, English, Family & Humor, chapters: 23, words: 24k+, favs: 22, follows: 15, 7/8/2013
5 ben and harry meet what happens now? by kaley the vampire lover basically what the tittle says R/R PLEASE! rated t for language that's all
T, English, Hurt/Comfort & Friendship, words: 951, favs: 6, follows: 4, 4/25/2013, Harry P., Ben T., Gwen T., Kevin
14 Harry Potter and the Plumbers » by Piece Bot What happens when the gang meets the Golden Trio?
T, English, chapters: 8, words: 4k+, favs: 15, follows: 15, updated: 1/26/2013 published: 9/30/2011, Harry P., Ben T.
51 Life Energy » by moonlitcat Harry's mother's mom was Gwen's grandmother's sister. What happens when he discovers his Andonite heritage? Slash. This idea came from DestroyerDRT.
T, English, Romance, chapters: 2, words: 2k+, favs: 265, follows: 329, updated: 12/4/2012 published: 9/19/2012, Harry P., Kevin
29 Harry Potter And The ET Discovery » by Potterformers Harry discovers the Omintrix and uses it to be free from the Dursleys, Maniputive Dumbles, starting of Harry/Ginny
T, English, chapters: 13, words: 15k+, favs: 135, follows: 105, 7/31/2012, Harry P., Ginny W.
17 Shit Happens by ProfessorEon During the Triwizard Tournament, Harry is gifted with both a great prize, and a great responsibility. Now, not only has Harry got a maniac Dark Lord after him, but now he has to fight against an Alien Overlord obsessed with retrieving the alien device on Harry's wrist, commonly known as the Omnitrix. Not only that, but Azmuth has Ben 10 searching for him. Rule 1: Shit Happens...
K+, English, Fantasy & Sci-Fi, words: 10k+, favs: 98, follows: 115, 7/14/2012, Harry P., Ben T.